P. D. James's dystopian novel The Children of Men has Theo Faron as its protagonist.
Theo is a historian living in England in 2021, in a world where human beings have become infertile. The government is controlled by his cousin Xan Lyppiatt, the Warden of England, while society declines under the pressure of population aging and the absence of children.
Theo is drawn into resistance politics through a group called the Five Fishes. His knowledge of history and personal connection to the ruling regime make him both an observer of the crisis and an unwilling participant in efforts to challenge it.
The 1992 novel is often confused with Alfonso Cuarón's 2006 film adaptation. The film retains the infertility premise and the name Theo, but changes major characters, events, and political details. Theo Faron is the specific name of James's literary protagonist.