When their friends are kidnapped, Sevan and Nadio find themselves marooned on the tourist Planet of Pallene. Their predicament gets worse when Republic troops transport them to a prison planet from which no-one has ever escaped. But escape is exactly what Sevan must do if he is to save the life of his friend, Nadio.

End of the Universe is the third novel in the light-hearted space opera series, Mastery of the Stars.