Watching a rented video, Tertuliano Maximo Afonso is shocked to notice that one of the actors is identical to him in every physical detail.

What begins as curiosity quickly hardens into obsession. Tertuliano tracks down his double, only to find a man whose existence destabilises his own identity entirely.

Saramago's novel explores the nature of individuality and examines the fear and insecurity that arise when our singularity comes under threat. For in this tense psychological literary thriller, the discovery of a double does not divide one life into two, it reveals that it was never singular to begin with.