"The Face in the Frost" is a fantasy novel written by John Bellairs, published in 1969. The story follows the adventures of a wizard named Prospero and his friend Roger Bacon as they navigate a magical world filled with strange creatures and dark forces. The plot centers around a mysterious face that appears in the frost, leading the characters on a quest to uncover its meaning. The novel combines elements of humor, magic, and friendship, making it a captivating read for both children and adults.