He finds himself on a strange world which is inhabited by bizarre tentacled creatures who claim to be the descendants of the human race.

Also present are many historical people who disappeared mysteriously, including the poet François Villon, King Arthur, the lost Dauphin, John Orth of Austria, and the Prophet Elijah.

Despite their technological prowess, the "future men" have lost certain human qualities – including love, loyalty and faith – which they now believe vital to their survival.

As the creatures suffer an attack by mindless monsters which they themselves created, John March and Evelyn Rand are transported back to 20th-century America.

March decides to publish a record of their experiences in the hope of changing the direction of human civilization.