After a meeting with friends at which it was agreed that each should produce a novel, the young Moravia began writing the story that would become Gli Indifferenti.

Moravia sent the manuscript to the editor of 900, a bilingual (Italian-French) review with which he had previously published some short stories.

Leo, the wealthy lover of Mariagrazia, a middle-class widow, begins an affair with her daughter, Carla.

Carla decides that she will sleep with Leo the following day (her twenty-fourth birthday) in order "to begin a new life".

Another English translation was published in Great Britain in 1953 under the title The Time of Indifference.