Remus John Lupin is a fictional character in the Harry Potter book series written by J. K. Rowling. He first appears in Harry Potter and the Prisoner of Azkaban as the new Defence Against the Dark Arts professor. Lupin remains in the story long after resigning from this post as a friend to the central character, Harry Potter. In the films, he is portrayed by David Thewlis as an adult, and James Utechin as a teenager.
