After killing his brother Abel, Cain must wander for ever. He witnesses Noah's ark, the destruction of the Tower of Babel, Moses and the golden calf. He is there in time to save Abraham from sacrificing Isaac when God's angel arrives late after a wing malfunction.

Written in the last years of Saramago's life, Cain wittily tackles many of the moral and logical non sequiturs created by a wilful, authoritarian God, forming part of Saramago's long argument with God and recalling his provocative novel The Gospel According to Jesus Christ.