What is the name of C.S. Lewis’s autobiography about his conversion?

Surprised by Joy is C.S. Lewis’s autobiography about his conversion.

Published in 1955, the book traces Lewis’s intellectual and spiritual development from childhood through his return to Christianity. It describes the role of imagination, literature, friendship, and philosophical reflection in that journey.

The title refers to Lewis’s idea of “joy,” a distinctive experience of longing or desire that he associated with moments of imaginative and spiritual insight. The autobiography does not simply present a chronological diary; it selects experiences that Lewis considered important to his development.

Lewis became a Christian in stages. He returned to theism in 1930, became a Christian in 1931, and later described conversations with fellow writers including J.R.R. Tolkien as influential. Surprised by Joy ends before his later fame as a Narnia author.