Which 1955 memoir by C.S. Lewis recounts his return to Christianity?

Surprised by Joy is C.S. Lewis’s 1955 memoir about his return to Christianity.

The book describes Lewis’s intellectual and spiritual development from childhood through his conversion. It is not a complete autobiography covering every part of his life; instead, it concentrates on experiences and ideas that influenced his changing understanding of faith, imagination, literature, and joy.

Lewis had been raised in the Church of Ireland but became an atheist in his adolescence. During his years at Oxford, conversations with Christian writers and scholars, including J.R.R. Tolkien and Hugo Dyson, helped challenge his assumptions. Lewis returned to Christianity in the early 1930s and later became one of its most prominent twentieth-century defenders.

The title refers to a form of longing that Lewis associated with moments of intense desire or delight. Readers should not confuse the book with A Grief Observed, which concerns his later grief after the death of his wife, Joy Davidman.