Plot

 

Part 1

 

 

Two spaceships, the Empress, a cruise liner, and the Hecate, a smaller ship, collide with each other, creating an unstable area where the two ships meet. The TARDIS materialises on the Empress, and the Doctor, Romana and K9 make their way to the bridge where they see the two captains, Rigg of the Empress and Dymond of the Hecate, arguing about their losses. The Doctor thinks he knows how to separate the ships. The Doctor and K9 go to the power unit, led there by Secker, who is acting strangely. He sneaks away, unknowingly followed by the Doctor and K9, and takes a drug out of a drawer. The Doctor gets into the drawer and finds the drug. K9 analyses it - it is vraxoin, a deadly drug.

 

Meanwhile Romana and Dymond go to the first class lounge and meet members of a zoological expedition - Tryst and his assistant Della. Tryst has specimens from various planets stored on his Continuous Event Transmuter (CET). Part of the machine includes a large screen that shows the planets he’s visited, but the planets onscreen are not just images. Romana understands the principle behind the machine - matter transference of dimensional control - and is not impressed.

 

The Doctor tells Rigg about Secker and the drug, and wonders about Tryst’s travels. He meets Tryst, who seems happy to meet another scientist. The Doctor learns that one of Tryst’s men died on the planet Eden. The Doctor and Rigg go to the power unit and use K9 to get to the source. Romana, alone in the lounge, plays with the controls to the CET. She looks at the projection of Eden and sees a face in the trees. Della comes in and tells her that Tryst would not like her using the machine.

 

Secker is looking for his drugs when he is attacked. He screams and the Doctor and Rigg find him. He has been cut by something and is taken to the sick bay. The Doctor goes to find Secker’s drug but is met by someone else who shoots him and takes the drug from the Doctor’s pocket.

 

Secker dies in the sick bay. Romana and K9 find the unconscious Doctor. When he wakes she tells him of what she saw in the CET. Romana heads back to the lounge while the Doctor, Rigg and K9 continue to cut through to the power source.

 

Something from the Eden projection comes out and hits Romana on her neck, causing her to lose consciousness. K9 has finally cut a hole in the wall to the power source, and when the Doctor and Rigg open the hole, a monster is behind the wall.

 

 

Part 2

 

 

K9 fires at the monster and they cover the hole. Back in the control room, Rigg scans the ship for vraxoin, with negative results. They make plans with Dymond to try to separate the two ships.

 

While Romana is unconscious, someone comes into the lounge and then leaves. Della comes in and helps Romana. The projection of Eden is now off. While Della gets a drink for Romana, someone pours vraxoin into the drink. Rigg arrives and she gives him the drink before making another one for Romana.

 

The Doctor gets some equipment from the TARDIS and goes to see Romana. Tryst arrives and the Doctor expresses his concern over the CET and lists several things wrong with it. Tryst shuts it off.

 

Back in the control room Rigg is being affected by the drug but no one realises. K9 goes into one of the unstable areas where the two ships are joined, while the Doctor waits for him. A strange man in glasses comes through the unstable area and runs away. The Doctor chases him. They run through the Empress and enter one of the unstable areas.

 

Rigg, affected by the drug, accuses the Doctor and Romana of being the drug smugglers. He also claims that the Doctor is a narcotics agent.

 

The Doctor is attacked by the man he was chasing, and comes face to face with another of the monsters. He comes out of the unstable area where Romana is waiting. The Doctor has found a radiation wrist band from the man he was chasing. It has the name Volante - Tryst’s ship - on it.

 

Tryst tells Della he thinks the smuggler was their crewmember who died - Stott. The Doctor and Romana learn that Rigg is affected by vraxoin. They go the CET, and Tryst offers to help. When Romana is sent away, Tryst tells the Doctor that Della is responsible for the drug smuggling.

 

The Doctor and Romana go to the control room, where agents from the Azurian Empire Customs question them about their involvement in the drug smuggling. One of them, Costa, searches the Doctor and finds traces of vraxoin from the sample he had in his pocket earlier. The Doctor and Romana run away, and are chased by Costa and his boss Fisk. They run to the lounge, where the CET is on and showing Eden. The Doctor takes something from the machine and they run into the projection.

 

 

Part 3

 

 

As the Doctor and Romana explore the projection, they discuss the problems with Tryst’s machine. The Doctor is attacked by a man-eating plant monster, but bites it in the root, which causes it to release him.

 

Back on the Empress, Tryst tells the agents that the selector for the machine is gone and he can’t turn it off.

 

The Doctor and Romana are attacked by one of the monsters, but are saved by a man who shoots the monster. He identifies himself as Stott, and the monsters as Mandrels. Taking them to a safe place, he tells them he works for the Space Corps’ Intelligence Section. He thought the Doctor and Romana were the drug smugglers, but overheard their conversation. He now thinks Secker may have been involved. The three of them leave the projection and end up on the Empress where K9 is.

 

On the Empress, passengers are being attacked and killed by Mandrels that have come out of the projection. Rigg is still acting silly and Fisk threatens to have him shot.

 

The Doctor works in the power room in order to separate the two ships. A Mandrel chases Romana into the room and then grabs the Doctor. K9 stuns it but the Doctor thinks it’s dead. He sends Romana to the bridge and K9 to the demat gun to await his signal.

 

Fisk arrests Rigg. Tryst asks Fisk not to kill the Mandrels. Fisk orders that the Doctor and Romana are to be found and, if they resist, shot. After they leave, the stunned Mandrel wakes up and attacks the Doctor. After chasing the Doctor, it is electrocuted when it hits the connections the Doctor has set up. It turns into dust which the Doctor identifies as vraxoin.

 

Romana reaches the control room. Rigg wants her to give him more drugs and attacks her when she can’t. Fisk enters and shoots Rigg. He tells Romana she is going to be killed, and tries to stop her touching the power controls.

 

The Doctor signals to Romana and K9 that he is ready. K9 activates the demat gun and Romana hits the power switch. The ships start to separate, everything shakes, and the Doctor vanishes.

 

 

Part 4

 

 

In the confusion, Romana escapes from Fisk. Now that the ships are separated, Dymond wants to go back to his ship but Fisk won’t let him - he is wanted as a witness.

 

Romana meets up with Della and tells her that Stott is alive.

 

The Doctor wakes up on the Hecate and discovers a laser. He hides from Dymond who has returned, and discovers on Dymond’s computer that he is involved in the drug smuggling. Dymond gets in a shuttle to return to the Empress, and the Doctor stows away.

 

The Doctor, on the Empress, is reunited with Romana and K9. Romana tells him the laser can send telecom messages and can also send a CET crystal. They realise that Tryst and Dymond are the smugglers.

 

The Doctor works on the CET machine, and Stott tells the agents that Tryst and Dymond are the smugglers. Tryst and Dymond temporarily hold Della, but when she escapes they shoot her. They head for the shuttle and back to the Hecate. Romana finds Della who is hurt but alive.

 

The guards have control of the Mandrels and herd them back to the projection. The Doctor lures them into the projection with the dog whistle. When he comes back out, they close down the machine. Romana has to rebuild the CET.

 

Part of the plan is to allow Tryst and Dymond to make their transfer. K9 locates the Hecate and the Doctor uses the machine to put it in the projection. Fisk’s men take Tryst and Dymond out of the projection and into custody.

 

The Doctor and Romana make their farewells and head off to return the electric zoo to their original planets.