The trio discover an empty 'leisure' biosphere. Behind the scenes a ruthless scientist works to produce humans strong and savage enough to survive anything they may find on their new home - at the expense of friendship and trust.

The angry, embittered Dr Richards tries to escape the Ark with his daughter after triggering the ship's self-destruct mechanism. His capsule fails to launch, and the self-destruct can't be overridden. But there is a very dangerous fix.