[Ortega in flight]

[Ortega flight deck]

(a light on the control panel flashes and beeps. Rafford activates the log recorder)
RAFFORD: (into log recorder) Log entry one-forty-three. Flight time zero-one-zero, elapsed nine-zero. We have reached course delta red two. New heading locked in, all systems functioning. Log entry closes.
(he inserts a star map into a viewer and is working on it when he hears somebody come in)
RAFFORD: Ah, come on in, I could do with some company. I feel sleepy all of a sudden. Just finishing marking up this.
(as he turns to see who it is he is knocked out. The attacker then smashes up the control panel with a mallet and leaves the flight deck)

[Liberator in flight]

[Flight deck]

JENNA: There it is, look, circling every two minutes.
BLAKE: When did you pick it up?
(they are looking at the plot moving across the viewscreen)
JENNA [OC]: Just before I called you.
BLAKE: It's circling all the time?
JENNA: Yes. Zen says it's a mark three Galaxy-class cruiser.
BLAKE: Galaxy-class? That's outer planets manufacture, isn't it?
JENNA: Right, but mark three went out of production at least fifty years ago.
BLAKE: Getting any signals from her?
JENNA: No, she's as quiet as a grave.
BLAKE: Probably guidance control systems.
JENNA: That ship's in trouble. It's the only thing that makes any sense.
BLAKE: Do you think so?
JENNA: Mm.
BLAKE: All right, we'd better take a look at her. Zen, abort course programs, Take us in two hundred spacials and match vectors.
ZEN: Confirmed.
BLAKE: I want everything in the data banks concerning Galaxy-class cruisers.
ZEN: Complete data is extensive.
BLAKE: Good. How long before we're in teleport range?
ZEN: That will depend on speed as yet unspecified.
BLAKE: Standard by four?
ZEN: Sixteen point one-four-zero-nine-zero-one minutes.
JENNA: Approximately speaking, of course.
ZEN: It is estimated that you will require one hundred and twenty-eight hours to assimilate all available data on Galaxy-class cruisers.
BLAKE: Mark three?

[Liberator turning in space towards the circling Ortega]

[Flight deck]

(the Ortega can now be seen on the viewscreen)
AVON [OC]: No sign of external damage.
BLAKE: According to the data banks, Galaxy-class cruisers are fitted with communicators. See if you can raise a voice contact, will you Cally?
VILA: I don't like this.
JENNA: That's unusual.
VILA: Mock if you like, but I can always sense danger.
GAN: Yes, even when there isn't any.
AVON: Scan doesn't show any modifications. I think it's just what it seems to be.
(in the background Cally can be heard trying to raise the Ortega)
BLAKE: An obsolete civilian cruiser. Any luck Cally?
CALLY: No response on any channel.
BLAKE: All right, I'm going across. Will you come with me, Avon, ...Cally? ...Vila.
VILA: You don't need me to come over!
BLAKE: No, I need you to work the teleport.
VILA: Right.
BLAKE: Zen, take us in to one hundred spacials and hold.
ZEN: Confirmed.

[Recreation room]

(Blake, Avon and Cally teleport into a room with a sofa and chairs at tables laid out with board games)
AVON: There you are, deserted.
BLAKE: (examining a chess board) If they did abandon, they certainly did it in a hurry.
AVON: If the last of this mark is built half a century ago, this ship could have been here a very long time.
CALLY: No, these space condition reports are recent.
BLAKE: There's an odd smell, sort of sickly-sweet.
CALLY: Yes, there is something.
AVON: Could be the change of atmosphere, a different recycle system to that of the Liberator.
BLAKE: No, it's more than that. I ...I can't place it. ...All right, shall we get on with it? You go on down towards the stern, Cally and I'll work up towards the flight deck.
AVON: Right, I'll just contact Vila. (into bracelet) Are you awake?
VILA: (on communicator) No.
AVON: That's what I thought. It's very quiet here. If it should get noisy, I'll be in touch.

[Yellow corridor]

(Blake and Cally, with guns drawn, open a door)
BLAKE: It's that same smell again.
(they open another door)

[Crew quarters]

(a man is laying on a bed and a woman is slumped by it)
BLAKE: The girl's alive.
CALLY: So is this one. The pulse is strong.
BLAKE: No visible sign of injury.
CALLY: Do you think they're drugged?
BLAKE: What?
CALLY: They could be drugged.
BLAKE: Possibly. ...I don't know, possibly. They're certainly in a coma of some sort.
(Cally begins to subside over the man and Blake becomes sleepy)
BLAKE: No, it's no good. We'll... we need the... ...Cally, that's it. Cally, wake up!
CALLY: (telepathic) Alone...
BLAKE: Yes, Cally!
CALLY: What?
BLAKE: It's Sonovapour. Tranquillising gas.
CALLY: Gas?
BLAKE: Yeah, that's why we're so sleepy.
(he closes a ventilator grille)
BLAKE: Must be bypassing the filters. I must find the filter system. ...That'll cut off the flow, it was coming through the ventilators.. Filters! See what you can do for those two.

[Green corridor]

(a door opens and Blake takes cover. Avon comes out)
BLAKE: Avon. Have you found anything?
AVON: Take a look.
(Doctor Kendall is slumped in a chair)
AVON: He's the fourth one I've found, all of them unconscious. It's ...Sonovapour.
BLAKE: Yes I know. We found a couple. It must be coming from the filters.
AVON: Yes, well that should be ...this way.

[Yellow corridor]

(Cally leaves Sara's quarters, looks through the windows of a couple of doors and moves on. She draws her gun when she is aware that the second door, which is the one to the flight deck, has slightly opened. As she cautiously opens it Rafford falls out)

[Filtration plant room]

BLAKE: It's over here.
AVON: Here it is.
(he removes a gas cylinder with a tubing connector)
AVON: Not a very expert job. Just stuck the tubing into the primary feed.
BLAKE: It's effective, though.
(Avon disconnects the tube)
AVON: Look at the gauge. The cylinder is almost empty.
BLAKE: Hm, once it was empty, the filter system would have cycled the gas out of the atmosphere.
AVON: At which point everybody would just wake up. On the face of it, a seemingly pointless exercise.
BLAKE: So wake them up and ask them what it's all about. Increase the oxygen supply, it'll speed recovery.

[Ortega flight deck]

(Cally comes in and examines a gas cylinder and tubing. She then hears Blake and Avon outside)

[Yellow corridor]

(Blake and Avon are kneeling over Rafford's body)
CALLY: He's dead.
BLAKE: Very.

[Ortega flight deck]

CALLY: Someone was very thorough. All this damage has jammed the main controls on a circular flight pattern.
BLAKE: Can it be repaired?
AVON: That would depend on what their replacement stores are like.
(Cally picks up the map viewer from the floor)
CALLY: Look at this - it's blood. He tried to write something.
AVON: Five-four-one-two-four. Whatever that might mean.
BLAKE: Could be anything. Call sign, transmission frequency, navigation index, anything.
CALLY: But it is important. He must have been dying when he wrote it.
(loud female screams are heard from the corridor)

[Yellow corridor]

(Sara, the girl from the crew quarters, is standing over Rafford's body)

[Liberator in space with Ortega circling]

[Recreation room]

KENDALL: I'm sorry, I just don't know. I haven't any answers to your questions. All I remember was I went my quarters and fell asleep in a chair. At least that's where I was when I woke up a few minutes ago and found all this going on.
BLAKE: Yes, I know exactly how you feel. Well, just relax and try to remember. Where were the rest of you when all this going on?
SONHEIM: What gives you the right to ask?
BLAKE: You need our help.
SONHEIM: Do we?
KENDALL: We do.
SONHEIM: I was off duty. I share quarters with Pasco.
PASCO: We were both there. Routine rest period.
BLAKE: And your name?
SONHEIM: Sonheim. We must have slept through it all, as Doctor Kendall did.
BLAKE: (to Grovane) You?
GROVANE: I was in the communications centre trying to make repairs. I remember feeling very drowsy, that's about all. And my name's Grovane. That's all.
SARA: Mandrian and I were together. The first thing I knew was when I came out into the corridor and saw Rafford.
BLAKE: And you?
LEVETT: I am called Levett.
BLAKE: Did you see or hear anything?
LEVETT: I was asleep in my quarters.
BLAKE: Would anybody else have seen you there?
SONHEIM: Why should anyone else bother.
PASCO: All right, there's no need for that.
LEVETT: There are worse things than being alone, Sonheim. Being with you is one of them.
KENDALL: We're getting away from the point a little, aren't we?
BLAKE: You were all knocked out by Sonovapour! Now sometime in the last twelve hours, your pilot was murdered. Now since you're the only people here on board, then I presume...
GROVANE: No we're not. Dortmunn isn't here.
BLAKE: Who is Dortmunn?
GROVANE: Flight engineer.
BLAKE: Well where is he?
KENDALL: I want him found, Mandrian. Search the whole ship. He's got to be here somewhere.
MANDRIAN: Sonheim, Levett.
BLAKE: Whilst your people look for him I'll go and see how my people are getting on. They're on the flight deck assessing the damage. Will you come with me?
KENDALL: Right.

[Ortega flight deck]

(Avon is removing damaged circuit boards with Cally looking on)
AVON: Well, there's nothing I can do with that, it'll have to be replaced.
BLAKE: What's the situation?
AVON: Well, we can fit some of it back together, but there are a lot of components that will have to be replaced.
KENDALL: Can it be made operational?
AVON: The interesting thing is as far as I can see that all this damage was done but for one purpose. To prevent the orbiting flight pattern which you are now in from being altered.
KENDALL: I don't understand any of this. First the trouble with the communicators, and now sabotage.
CALLY: What happened to the communicators?
KENDALL: Just after we started back on the return trip there was a burnout in the main circuits. Grovane, the communications officer, thought the damage couldn't be accidental. Apparently, all the safety circuits were still intact. They'd been bypassed somehow. It's still not working.
(Avon removes a crystalline sphere from the control panel)
BLAKE: This man Dortmunn they're looking for. Could he have any reason to sabotage you?
KENDALL: None that I can think of. He's a fine man and a first class engineer.
(Kendall's personal communicator buzzes)
KENDALL: (into communicator) Kendall.
MANDRIAN: (on communicator) Mandrian. We're in section nine, Doctor, you'd better come down. There's something you should see.
BLAKE: Lead the way.
AVON: This is a pity.
(showing the crystalline sphere to Cally)
CALLY: What is it?
AVON: The Ison crystal. Even if we should get the ship operational, it will be blind. With this fractured, there isn't a chance of outside vision.

[Red corridor]

KENDALL: What have you found?
SARA: Life rocket two has been launched.
BLAKE: That explains where Dortmunn got to.
MANDRIAN: He's taking a tremendous chance. Those life rockets have a limited range. It certainly couldn't carry him to the nearest habitable planet.
KENDALL: But why? Why would he do that?
BLAKE: If he killed Rafford, he's got nothing to lose. A ship this size, you can't hide forever.
KENDALL: It still doesn't explain why. Not just the murder, the malicious damage. ...It's not possible. ...I'd better check just to be sure.

[Kendall's quarters]

(Kendall opens a security safe and a box from it which contains a transparent green tube)
KENDALL: For a moment, I thought Dortmunn might have taken it. If he had, everything that has happened would have made sense. But it's here. It had to be, of course. It's impossible to open the safe without a molecular key and combination, and I'm the only one on the ship that has those.
BLAKE: Well, what is it?
KENDALL: It's an energy refractor, a neutrotope.
BLAKE: What does it do?
KENDALL: I'll explain. I and my crew come from Destiny,...
(he points to a star chart on the wall)
KENDALL: ...way out here on the edge of the galaxy.
BLAKE: Yes, I've heard of that. It was colonised what, about a hundred years ago?
KENDALL: That's right.
BLAKE: But you're still not members of the Federation?
KENDALL: They've approached us, threatened, but we've resisted so far.
BLAKE: Hm.
KENDALL: Ours is an agricultural economy. We've a small fleet of mercantile ships to trade with our nearest neighbours. Our people live well, but simply. At least they did.
BLAKE: What happened?
KENDALL: Towards the end of the last growing season, just as the main crop was coming into maturity, reports came in that the plants were dying, wilting and dying. It spread across both our continents with incredible speed. We estimated that in under a year there would be no living vegetation left on the planet.
BLAKE: But did you isolate the cause?
KENDALL: It was a fungal disease. Identifying it was one thing, but destroying it? ...It was resistant to everything. In under three months, half the planet was buried in a covering of slimy white fungus. The stench was vile and it was still spreading.
BLAKE: And you think this, er, neutrotope will provide the answer?
KENDALL: My experiments show that radiation from our sun was deficient in certain specific wavelengths. The neutrotope will provide the necessary frequencies to kill the fungus.
BLAKE: And you'll mount this on a satellite to be activated by your sun?
KENDALL: That's right.
BLAKE: Hm.
KENDALL: We've calculated the orbital pattern required to maintain a balance and save our planet.
BLAKE: Impressive.
KENDALL: Yes, this has cost us ...well, let's say it's bankrupted our economy and mortgaged our future.
BLAKE: Why so much?
KENDALL: The yield from the ore containing the element is minute. This neutrotope and the few others that exist are the most valuable objects in our galaxy.
BLAKE: Yes, well I can see why you were concerned that Dortmunn might have taken it.
KENDALL: Yes, it's enough to tempt anyone. There are men who would betray their companions for a lot less.
(Avon has come in)
AVON: What a very cynical thought, Doctor.
KENDALL: But realistic, I'm afraid.
AVON: Cally and I have finished checking the damage. I can give you a fairly accurate assessment of the situation now. We can fit things together and we can make repairs.
BLAKE: And?
AVON: There is, however, ...a problem.

[Recreation room]

AVON: When we've finished, you should have a ship that will navigate and get you back to Destiny. The problem, is that without this, (holding up the Ison crystal) you will have to travel at sub-light speeds. I estimate that the journey will take you approximately five months to complete.
SONHEIM/GROVANE: But that'll be too late!
AVON [OC]: Five months.
SONHEIM: We'll miss the planting season!
GROVANE: It'll set us back a full year!
KENDALL: When I heard the news I was concerned as you are. A delay that long would be disastrous, but there is an alternative.
BLAKE: Liberator can make the journey in four days, ...and what I've suggested is that Avon and Cally stay here and help you with your repairs. I take the neutrotope to Destiny, and then come back to collect them.
MANDRIAN: No. We can't do that. We can't just hand over the neutrotope to some passing stranger.
SONHEIM: I agree. We've been trusted with this mission, we can't simply forget our responsibility.
MANDRIAN: There are plenty of ready markets for the neutrotope. If it was stolen and sold, a man could be wealthy beyond ...beyond imagining. That thing is a temptation even for those of us with our homes, families, and lives at stake. You have nothing at stake, nothing to lose.
AVON: It is frequently easier to be honest when you have nothing to lose.
BLAKE: The responsibility for the neutrotope belongs to all of you. There is a risk that if you entrust it to me, I may fly off never to be seen again. You have to weigh that chance against the effects a year's delay would have on the possibility of your planet's recovery. We made the offer, the choice is up to you.
CALLY: Remember that Avon and I will be staying. We will regard ourselves as hostages against Blake's return.
AVON: Well thank you Cally. What a clever idea.
CALLY: (telepathic) Blake will return.
AVON: You can bet your life on it, in fact you've just bet both our lives on it.
KENDALL: Well personally, I have no hesitation about accepting the offer. Delivery of the neutrotope is vital. And anyway, after what's happened here, it may well be safer with Blake. However, we'll vote on it. Those in favour?
(Kendall, Levett, Pasco and Grovane raise their hands one after the other. Sara then begins reluctantly to raise hers but puts it down when Mandrian glares at her)
KENDALL: That's about four to three, in favour. We accept gratefully.
BLAKE: Right, I'd like to get started right away.
KENDALL: Of course. Sara, would you get the neutrotope, please?
(Mandrian storms out after Sara)
KENDALL: Sorry.
BLAKE: It's all right, it's a natural reaction. Right, I'll get back to you as soon as I can.
(Avon and Cally hand their teleport bracelets to Blake)
BLAKE: You're quite sure about volunteering to stay?
CALLY: We must help these people.
AVON: Must we? Personally, I don't care if their whole planet turns into a mushroom. I shall stay because I don't like an unsolved mystery.
BLAKE: You don't think Dortmunn and his life rocket are the answer?
AVON: No.
BLAKE: Why not.
AVON: There is something else that has to happen before it all begins to come together.
(Sara returns with the neutrotope box and gives it to Blake)
BLAKE: Thank you. (to Avon and Cally) You better give me your guns.
KENDALL: Don't fail us.
BLAKE: I won't. (into bracelet) Vila, bring me up.
CALLY: My people have a saying, 'A man who trusts can never be betrayed, only mistaken'.
AVON: Life expectancy must be fairly short among your people.

[Flight deck]

(Jenna is reading the numbers out and punching them into a control pad while Gan operates one of the control consoles)
JENNA: Three-two point one-oh.
GAN: Check.
JENNA: Three-two-one-oh-oh.
(Blake and Vila come in)
VILA: Where are Cally and Avon?
BLAKE: It's a long story.
VILA: Well what's in the box?
BLAKE: It's an even longer story.
VILA: I like stories!
BLAKE: Zen, get a locator fix on the other ship. I want to be able to pinpoint its position at all times.
ZEN: Confirmed.
BLAKE: Set a course for Destiny, speed standard by six.
VILA: Where's that?
ZEN: Confirmed.
GAN: (indicating the neutrotope box) What have you got there?
JENNA: Why are we leaving them behind? What's going on?
VILA: Where is Destiny?
BLAKE: According to Avon, it is a story that doesn't have an end yet.
VILA: All right then we'll start with the beginning.

[Liberator moves off from the circling Ortega]

[Ortega flight deck]

AVON: Probe.
(Levett hands the tool to him. Meanwhile Cally is holding the map viewer mouthing five-four-one)
CALLY: ...two-four. Does this mean anything to you? Five-four-one-two-four?
GROVANE: No, I don't think so.
LEVETT: Should it? Is it important?
CALLY: Yes it is important.
AVON: (to Grovane) Monitor response?
(Grovane goes over to an equipment rack)
CALLY: The air is stale in here.
LEVETT: The ventilator's closed.
(Cally opens the ventilator)
AVON: (to Grovane) Well?
GROVANE: Zero response.
AVON: Well there is nothing I can do. It will have to be replaced. I shall need laser transfer linkage. Have you got any?
LEVETT: I think so, in the storage hold. I'll go and check.
CALLY: Stay here, I'll get it.
LEVETT: You'll need a torch.

[Yellow corridor]

(Cally hears a metallic clicking sound coming from Mandrian's quarters)

[Crew quarters]

(Mandrian is tapping a small electrical device and seems to be trying to open it. Cally watches. Having apparently failed to achieve what he wants, he puts it into a flight bag which he puts under the mattress and leaves. When he has gone, Cally retrieves the device and pockets it)

[Recreation room]

(Sonheim is consulting a reference pad. Pasco is using a tool, which hums, on a small piece of equipment)
PASCO: Fourteen?
SONHEIM: Right.
CALLY: (comes in) Where is the storage hold?
SONHEIM: What do you want down there?
CALLY: We need some laser transfer linkage.
SONHEIM: I don't know that we have any.
CALLY: Well, that is what I'm going to find out. (to Pasco) Can you tell me, please?
PASCO: Don't mind him, he lacks affection. Blue corridor. Go down past the filtration plant and it's the next door on the left.
CALLY: Thank you.
SONHEIM: Be back in a moment.

[Blue corridor]

(Cally hears an argument coming from the filtration plant room)
SARA [OC]: ...You are always snooping.
MANDRIAN [OC]: I am not snooping.
SARA [OC]: Yes you are!
MANDRIAN [OC]: I am not! Now I want to know what it is.
(Sara runs out, apparently not noticing Cally, and rushes away. Cally eases the door open. Mandrian is slumped against a wall with his head in his left hand. She finds the storage hold and, as she goes in, Sonheim appears round the corner)

[Storage hold]

(Cally searches the storage hold using a torch. Having opened a cupboard, and while looking inside, there is a noise and an arm drops down from the top and a body falls off onto the floor. As Cally looks at the body, Sonheim who has come in, puts his hands on her shoulders. She jumps and backs away. Sonheim turns the body over)
SONHEIM: It's Dortmunn.

[Recreation room]

KENDALL: Someone among us determined that this mission should fail, and frankly I can't even guess at a motive.
AVON: Try greed. It's usually reliable. When you set out on your return journey, you were carrying something extremely valuable. (indicating Mandrian) As he said earlier, if the neutrotope could be sold, it would make a man wealthy beyond imagining. Well, it obviously wasn't beyond the imagination of someone here.
MANDRIAN: I just meant that we were taking an enormous risk by entrusting it to a stranger. It never crossed my mind that any of us...
AVON: But it did cross your mind, didn't it? A temptation, you said, even for those of us with our lives at stake. ...The value of the neutrotope is all the motive you need to look for. Now I don't pretend to know the whole plan, but parts of it seem fairly clear. The damage to the communications centre. That isolated the ship. You couldn't receive any messages, nor could you put out a distress call. I'm not sure when Dortmunn was killed, but Cally thinks that the death of the pilot, Rafford, was an accident.
ORTEGA CREW: (in unison) What d'you mean?
SARA: An accident?
CALLY: A misfortune.
AVON: It certainly was for him.
CALLY: I think that it was not part of the plan. Whoever put the Sonovapour into the ventilation system intended to put the whole crew to sleep, while the controls were being sabotaged. Rafford was supposed to be sleeping too.
AVON: But the ventilator ducts on the flight deck were closed. Consequently Rafford was unaffected by the gas.
CALLY: The murderer was using an oxygen mask to stay awake. Reaching the flight deck and finding Rafford conscious must have been a shock.
AVON: And that shock killed Rafford.
PASCO: The ventilators shouldn't have been closed. It's against flight operating procedure.
AVON: The next shock was when we arrived. Now that that really was misfortune. Pure bad luck.
PASCO: Rafford should have known better.
SARA: Shut up, Pasco!
MANDRIAN: Go on.
AVON: Even the most meticulous of plans could not have anticipated our arrival.
LEVETT: Meticulous?
AVON: The murderer had to cover up, and quickly. Dortmunn was killed. I think the plan was to put his body into the life rocket and launch it into space. That way, it would appear obvious that Dortmunn was guilty.
SONHEIM: So why didn't it happen?
AVON: I think it was too difficult. Dragging the body across the spaceship, to the launch area without being seen. That proved to be impossible, so the murderer settled for the next best thing, He launched an empty life rocket, ...and that worked. We all believed that Dortmunn had escaped.
MANDRIAN: But whoever did it must have known the body would be discovered sooner or later.
AVON: Of course. He was playing for time. The plan had gone to pieces. The best the killer could hope for was to delay a full inquiry for as long as possible. As a matter of fact, I think that was a waste of effort. I know, ...we all know, that one of you is the murderer. But proving which one, ...unless, of course, as seems quite likely, someone other than the murderer already knows. ...Already knows.
KENDALL: Naturally, the whole matter will be put into the hands of the authorities when we reach Destiny. Despite what you say Avon, the murderer will be found. In the meantime, you will all resume your normal duties, and anything that you see or hear that seems unusual, report to me at once. Thank you.
(all the Ortega crewmembers except Kendall and Grovane leave)
AVON: We'll get back to the repairs now. A couple of hours, you should be able to set off for home.
KENDALL: Something you wanted, Grovane?
GROVANE: Yes. It just occurred to me. ...You said one of us is the murderer.
AVON: That's right.
GROVANE: There is another possibility.
AVON: Yes?
GROVANE: There could be somebody else on the ship, somebody we don't know about. ...A stowaway!

[Liberator in flight]

[Flight deck]

(Gan wakes Vila and hands him and the others a drink)
ZEN: Detectors indicate a meteorite storm directly in Liberator's flight path.
BLAKE: Scale, intensity?
ZEN: Scale nine, intensity twenty-seven.
VILA: Twenty-seven?
GAN: I think eight's about the strongest we've had so far.
JENNA: My teeth are still rattling from that.
VILA: An intensity of twenty-seven is a lot of very fast rocks.
BLAKE: Scale nine puts the storm over a vast area too. How much would it add to our flight time if we went around it?
ZEN: Estimated flight time of eighty-four hours would increase to three hundred and thirty-six hours.
VILA: Ah.
JENNA: Four times as long.
ZEN: Confirmed.
BLAKE: Would the force wall hold if we went straight through the storm?
ZEN: It is within the maximum design tolerance, however there would be no safety margin.
BLAKE: Is there enough reserve power to maintain the wall?
ZEN: Insufficient data for accurate projection.
JENNA: In other words, he doesn't know.
ZEN: Confirmed.
VILA: Let's go round.

[Blue corridor]

(Cally comes out of the storage hold with the transfer linkage)
CALLY: Are the others still searching?
SARA: Yes, nothing so far. Do you want any help on the flight deck?
CALLY: No, we've almost finished. Sonheim, there was something I wanted to ask you.
SONHEIM: (to Sara) Go ahead, I'll catch you up. ...(to Cally) What is it?
CALLY: Finding Dortmunn's body put it out of my mind. Why did you follow me to the storage hold?
SONHEIM: Why do you think? You're an attractive girl. You asked where the hold was, I snapped at you. I came after you to ...apologise?
CALLY: To apologise?
SONHEIM: Of course. What other reason could I have?
CALLY: Perhaps you were afraid I would find Dortmunn.
SONHEIM: That's ridiculous! I didn't know his body was there! I told you! I followed you to apologise!
CALLY: I believe you.
SONHEIM: It's true!
CALLY: Of course.

[Ortega flight deck]

CALLY: The transfer linkage you asked for.
AVON: About time. Any news from the search parties?
CALLY: No.
AVON: No, there won't be. It was an unlikely idea, keeping out of sight for the length of time this ship has been in flight. Not really possible.
CALLY: I agree. So who do you think it is?
AVON: Mandrian.
CALLY: Why?
AVON: Instinct. I discount Doctor Kendall.
CALLY: I thought you mistrusted instinct.
AVON: I do, so I am probably wrong.
CALLY: It could be him. I told you I heard him quarrelling with Sara, didn't I? ...Sonheim makes me uneasy, too.
AVON: He would be next on my list.
CALLY: The answer is here, ...if only we could see it.

[Blue corridor]

(Mandrian goes into the filtration plant room)

[Filtration plant room]

(to someone unseen)
MANDRIAN: I knew you'd be here.

[Flight deck]

(the meteorite storm is on the viewscreen)
BLAKE: How far are we in now?
VILA: Halfway. I can't be sure. The detectors are swamped.
GAN: The force wall's eating into our power reserves.
JENNA: There's a field drag effect too. We're having to use a lot of power to maintain our speed and heading.

[Ortega flight deck]

(Cally is holding the small electrical device)
CALLY: Avon, I saw Mandrian with this. Then he put it back in the bottom of Sara's flight bag.
AVON: What is it?
CALLY: Well, that's what I want you to tell me.
(the main light go out and an alarm sounds. Cally points to alarm lights on the control panel)
CALLY: Look!
AVON: Filtration malfunction. We'd better get down there.

[Yellow corridor]

LEVETT: Doctor Kendall wants you.
AVON: Filter plant?
LEVETT: There's been another killing.

[Filtration plant room]

(Sara is sobbing on Doctor Kendall's shoulder, Mandrian is lying on the floor and Pasco and Grovane are restraining Sonheim. A burnt cable smokes and splutters)
AVON: Tell me what happened.
PASCO: I was coming past, and I heard a noise, so I looked inside. Mandrian was just as you see him. Sonheim was standing over him, with this dagger in his hand.
SONHEIM: I didn't kill him. I didn't kill him. I didn't kill him! (to Avon) I didn't kill him!!

[Flight deck]

GAN: Power reserves are almost gone.
ZEN: In one point zero-three minutes, it will no longer be possible to operate force wall and main drive simultaneously. Please decide which to close down.
JENNA: Without main drive we'll never get out of this.
VILA: Without the force wall we'll be smashed to pieces.
BLAKE: Have the locators detected the outer edge of the storm yet?
VILA: No. Yes! No. Maybe...
BLAKE: Which is it, Vila?
VILA: It's `Maybe'.
ZEN: Directive is now required.
BLAKE: Jenna, stand by to feed all power through to the main drive when the force wall is down. Gan, deactivate the force wall.
GAN: Deactivating...
(as Liberator accelerates the neutrotope box falls off a table)

[Recreation room]

KENDALL: Why? For what reason?
CALLY: Perhaps Sonheim is still trying to cover up. Mandrian knew about him and threatened to expose him. Or perhaps he went into the filter plant while Sonheim was sabotaging the equipment?
KENDALL: But why damage the filter? What possible reason could he have for delaying the flight still further?
(Avon, Pasco and Grovane come in)
CALLY: How bad it is?
AVON: The damage was minor. I've got Levett working on it.
PASCO: We've locked him in the storage hold. He seems quiet enough.
CALLY: Has he said anything more?
GROVANE: Well, nothing new. He claims he went in and found Mandrian dead, picked up the knife, that's where I came in. He still says he didn't kill him.
AVON: I believe him.
GROVANE: But I saw him with a dagger in his hand!
AVON: But you didn't see him use it.
GROVANE: Well, I didn't see Mandrian die either, but I know he's dead.
AVON: I've just spent the last ten minutes in the filter plant looking for something that should be there but isn't. The cable that was damaged carries a high-energy charge. In order to cut it, he would need a laser knife or an insulated saw, neither of which were there.
KENDALL: Then, somebody else was the saboteur?
AVON: Yes. Mandrian came in, discovered whoever it was, and had to be silenced. The murderer then went out, taking the saw with him. Sonheim's story is true, he just happened to be the one to discover the body.
SARA: Then who did kill Mandrian?
AVON: The same person who killed Rafford and Dortmunn, and I know who that is now.
GROVANE: You know?
AVON: Yes. I should have seen it right from the start, but my mind had conditioned itself to see the wrong thing. ...As Cally has been saying all along.
(Avon produces the top of the map viewer with the numbers on it)
CALLY: You found the meaning!
AVON: Yes. Just before he died Rafford managed to scrawl this out.
KENDALL: Five-four-one-two-four?
AVON: Precisely.
PASCO: What's it mean?
AVON: Absolutely nothing. As a number it has no significance at all, but when I was in the filter plant just now, I noticed one of the instruments. Liquid crystals show a number, and then the confirmation circuit translates those numbers into the written word. Right from the start, we thought that those were numbers. They are not, they are letters.
CALLY: Letters?
AVON: Rafford was dying. It's difficult to be neat under those circumstances.
(he takes a paper and a pen)
AVON: Let's start with the one and the two.
(he writes the one and the two to make an R, the fours either side of the R as A's making ARA)
AVON: And the first letter...
(he adds the five as an S in front making SARA)
SARA [OC]: So now you know.
(they all turn to find Sara covering them with a gun)
SARA: It doesn't matter, you'd have known soon enough anyway.
KENDALL: Sara! Why?
SARA: I wanted the neutrotope, or at least the money it would give me. It's that simple.
AVON: Was Mandrian in it with you?
SARA: No, but he found out. I asked him to share it with me, but he wouldn't. He wanted me to come to you and admit the whole thing. If I didn't, he was going to tell you himself. So... But none of that's important now, I only need a little more time.
AVON: You're not going anywhere, Sara. You just don't get off a spaceship and run.
SARA: I'll kill the first one that puts his head outside this door.

[Green corridor]

(Sara runs down the corridor and round a corner. Avon looks out)

[Recreation room]

AVON: Well, she's one of your crew, you'd better get after her.
(Pasco and Grovane run out)

[Yellow corridor]

(Sara goes through the door into the flight deck. Pasco and Grovane arrive and try the door)
PASCO: Locked!

[Recreation room]

KENDALL: It's clear enough why she acted as she did, but why go with it? Once Blake left with the neutrotope, there was no need for more killing.
AVON: I don't understand that myself. What worries me is that she's still so confident. She hasn't a hope of escaping yet she's still holding out.
KENDALL: How did she hope to dispose of the neutrotope when we reached Destiny?
AVON: She probably made contact with a prospective buyer when you were collecting it. It wouldn't be too difficult.
(Cally suddenly stands up)
AVON: What is it?
CALLY: I know what she's planning. Why she sabotaged the ship.
AVON: Well, don't keep us in suspense.
(Cally gets the electrical device out of her pocket)
CALLY: Ever since the controls were damaged we have in the same space position.
(she hands the device to Avon)
AVON: A homing beam transmitter and it's operating.
CALLY: Anyone tuned into its frequency can locate us exactly. That's why she's not worried. Another ship is coming to get her and it's on its way now.
KENDALL: Destroy it!
AVON: Too late. They will have had a fix on us for some time now.
KENDALL: And when they get here and find the neutrotope not on board?
AVON: It wouldn't matter if it was. They will have to destroy the evidence, and that, I'm afraid, includes us.

[Liberator in flight]

[Flight deck]

VILA: I don't think I feel very well.
(Blake and Gan have put the neutrotope box back on the table)
GAN: I hope nothing's been broken.
BLAKE: So do I.
(Blake opens the box. It's empty)
BLAKE: It's still on the Ortega. We've got to get back to them.
VILA: Now I know I don't feel very well.

[Yellow corridor]

(Grovane and Pasco, armed, are on guard outside the flight deck door)

[Ortega flight deck]

(Sara is sitting at control panel with the transparent green tube containing the neutrotope in her hands. She puts it down and picks up her gun)

[Red corridor]

CALLY: If we could get back onto the flight deck, how long would it take to finish repairs?
AVON: No time at all. It's virtually all done.
CALLY: In flight we'd stand some sort of chance, like this we're a sitting target.
KENDALL: We would have to burn through the flight deck door, and if we did, she's armed, remember. She could still hold us off.
AVON: Then we have to get her to come out.
CALLY: Well she's hardly likely to do that.
AVON: Oh yes she is.

[Liberator in flight]

[Flight deck]

BLAKE: Visual.
ZEN: Confirmed.
VILA: There, there she is.
(the trace of the Ortega can be seen circling on the viewscreen)
BLAKE: How long before we're in teleport range?
ZEN: Twenty-three point one-six minutes.
GAN: We're getting another reading!
BLAKE: What?
GAN [OC]: Look!
(another trace is approaching the Ortega on the viewscreen)
JENNA: Another ship.
BLAKE: It must be coming to collect the neutrotope. Zen, can we get there first?
ZEN: Liberator will be in teleport range three minutes before the unidentified ship makes contact with the Ortega.

[Ortega flight deck]

(there are muffled sounds of blasts and screams outside in the corridor)

[Yellow corridor]

(Cally's hands are seen firing an Ortega gun)

[Ortega flight deck]

(when all is quiet, Sara opens the door and finds Grovane and Pasco laying there)

[Yellow corridor]

(Sara comes out. Avon comes out a door behind her and grabs her, disarming her. They struggle. Pasco and Grovane begin to get up. Avon manages to land a punch on Sara's chin. Pasco and Grovane restrain her)
AVON: You'd better get her out of here, I really rather enjoyed that.

[Ortega flight deck]

(Avon comes in and picks up the tube containing the neutrotope)

[Flight deck]

ZEN: Teleport range will be achieved in one minute.
BLAKE: Come on, Vila.
JENNA: They're getting very close.
(looking at the viewscreen)

[Recreation room]

(Blake teleports in carrying a large box an a bunch of bracelets)
AVON: Blake!
CALLY: How did you get back so soon?
(Blake puts the bracelets on the table)
BLAKE: Get ready to leave. There's a ship coming up on you fast. You've got about three minutes.
KENDALL: We have the neutrotope now, nothing else matters.
CALLY: I'll get the others.
BLAKE: I'll be back in a minute.
(he leaves still carrying the large box)

[Flight deck]

[Flight deck]

(the two traces are on the viewscreen)
GAN: He's cutting it too fine.
JENNA: Come on Blake, get out of there.

[Recreation room]

(Sara is struggling with Avon and Sonheim. Avon is trying put a teleport bracelet on her wrist)
SARA: No, no I won't!
KENDALL: She must be taken back for trial.
AVON: Agreed.
SARA: I won't go! I won't go.
BLAKE: Everything set?
CALLY: Yes, ready.
(Sara rips off the bracelet and throws it away)
BLAKE: (into bracelet) Bring us across Vila.
(Sara is left behind, smiling)

[Flight deck]

(the two crews are watching the viewscreen)
BLAKE: They're locked on.
(as the traces merge there is a huge explosion)
KENDALL: What was that?
BLAKE: I rigged a charge on the entry hatch. Right, I think I can get you all home now. Zen, set a course for Destiny, speed standard by six.
ZEN: Confirmed.
VILA: Take us round the easy way this time.