(BARBARA runs up to them.) (To a VOORD.) And his life's work destroyed. CELL
(IAN looks up at the clock, the hand of which is getting ever closer to the star.) COURTROOM RECEPTION (LATER)
(The travellers have all been reunited except for IAN.) Come on. He is of no use to you. ISLAND
(The TARDIS dematerialises from the island and from Marinus itself.) If he does it will set the machine in motion, but once it feels the full force of the power it ... it'll break under the strain. SUSAN: Arbitan! TARRON: Call the prison. Who? YARTEK places the four keys into slots in the Conscience machine. YARTEK: There are many races of men on Marinus.
Plan: A: The TARDIS; Q: What ship arrives on the planet Marinus? A: the planet Marinus; Q: Where does the TARDIS arrive on an island of glass surrounded by a sea of acid? A: The travellers; Q: Who is forced by the elderly Arbitan to retrieve four of the five operating keys to a machine called the Conscience of Marinus? A: the keeper; Q: What is Arbitan's role in the Conscience of Marinus? A: their own sinister purposes; Q: What do the evil Yartek and his Voord warriors plan to use the Conscience of Marinus for? Summary: The TARDIS arrives on the planet Marinus on an island of glass surrounded by a sea of acid. The travellers are forced by the elderly Arbitan to retrieve four of the five operating keys to a machine called the Conscience of Marinus, of which he is the keeper. These have been hidden in different locations around the planet to prevent them falling into the hands of the evil Yartek and his Voord warriors, who plan to seize the machine and use its originally benevolent mind-influencing power for their own sinister purposes.