An electronics engineer, Sakharov, despairing of the slow death which he believes in store for all inhabitants of the Ark, bypasses the fail-safe mechanisms in order to activate the Ark's self-destruct system. In doing so, he inadvertently trips the fail-safe alarms, alerting Devon, Rachel and Garth. Sakharov, with his daughter Valarie (who opposes his plan) intends to escape the Ark at the last moment aboard the rocket designed to jettison the Ark's logs and cassette recordings of Earth history prepared, 'for the benefit of other life in the universe'. But when the rocket fails to leave, Sakharov, with Devon and Garth's help, undertakes to rewire the fail-safe and stop the self-destruct. Since all the mechanisms are in micro circuits, they must be projected miniaturized into the circuits through an astounding electronic procedure. It is a race against time to re-connect the minute circuits before the whole Ark blows.

• Harlan Ellison

• Keir Dullea
• Robin Ward
• Ed Ames