What was the title of C.S. Lewis’s 1933 autobiographical novel about conversion?

The Pilgrim’s Regress was C.S. Lewis’s 1933 autobiographical novel about conversion.

The Pilgrim’s Regress: An Allegorical Apology for Christianity, Reason and Romanticism follows a character named John on a journey through a landscape filled with symbolic figures and places. Lewis wrote it after his return to Christian belief, and the book reflects his struggles with philosophy, reason, desire, and religious commitment.

Lewis later said that the allegory was difficult for some readers because its references were not always obvious. His later memoir Surprised by Joy gives a more direct account of his intellectual and spiritual development, but it is not a novel. The Pilgrim’s Regress therefore belongs to both Lewis’s early fiction and his early Christian writing.