Milligan is a secret agent who was brainswept by Ledroptha Curtain, causing him to lose his memories. He later regains them, and then remembers that he is Kate Wetherall's father. He is almost always in disguise as something or other; in fact, he can change disguises in less than a minute, going from short and fat to tall and exceptionally thin. It's reasonable to believe, however, that he resembles Kate (or she resembles him), and we know for certain that he has blue eyes, is very tall, and has blonde hair that is bright yellow.