Mike Hanlon is a fictional character from Stephen King's novel It. He is one of the seven members of the Losers' Club, a group of children who come together to confront a malevolent entity that preys on the town of Derry, Maine. Mike serves as the group's historian, documenting their experiences and the history of the creature known as Pennywise. As an adult, Mike becomes the town librarian and is the one who remembers the events of their childhood. He is determined to bring the group back together when It returns to Derry, showcasing his loyalty and commitment to his friends. Mike's character represents the themes of memory and the importance of facing one's fears.