While visiting a diner in Nevada in 1958, the Doctor finds an alien artifact and ends up on a mission to save the Rivesh Mantilax from the danger of the Viperox and the U.S. Military.

The doctor and his companion, Evelyn, investigate a series of mysterious disappearances on the planet Chronos.

The Doctor and Martha Jones trek through space and time in a race against the galaxy's greatest despot, Balthazar, to follow a complex trail of clues to discover the location of the legendary lost spaceship, the Infinite, which, according to myth, can grant anybody their hearts desire.