The cantankerous caretaker at Hogwarts. He has a cat, Mrs. Norris, who helps him patrol the corridors. He doesn't like students, suspects them all of mischief, and is a fan of horrific corporal punishment that in the novel's present is illegal. Fred and George share with Harry that Filch has a drawer full of potentially dangerous confiscated items, from which they stole the Marauder's Map in their first year.