Set in the 1950s, the film focuses on reserved, middle aged bachelor C. S. Lewis, an Oxford University academic at Magdalen College and author of The Chronicles of Narnia series of children's books, and his relationship with divorced American poet Joy Gresham and her young son Douglas. What begins as a formal meeting of two very different minds slowly develops into an intense feeling of connection and love. Lewis finds his quiet life with his brother Warnie disrupted by the outspoken, feisty Gresham, whose uninhibited behavior offers a sharp contrast to the rigid sensibilities of the male-dominated university. Each provides the other with new ways of viewing the world. Initially their marriage is one of convenience, a platonic union designed to allow Gresham to remain in England. But when she is diagnosed with cancer, deeper feelings surface, and Lewis' faith is tested as his wife tries to prepare him for her imminent death.