Jamie Madrox is a fictional character in the Marvel Comics universe, known as the superhero Multiple Man. He first appeared in Giant-Size Fantastic Four #4 in 1975. Jamie has the unique ability to create duplicates of himself, allowing him to be in multiple places at once. Each duplicate has its own personality and memories, which can lead to complex situations. As a member of the X-Men and X-Factor, Jamie often grapples with the challenges of his powers, including the emotional and psychological effects of his duplicates. His character explores themes of identity and self, making him a compelling figure in the Marvel storyline.