Hal Tucker is a fictional character in Monk. He debuted in the episode"Mr. Monk is at Your Service". In "Mr. Monk Makes a Friend" he was the main antagonist in that episode. He feigns befriending Adrian Monk at the beginning of the episode so he can get to a crime scene, at which he committed a crime but made a mistake.
He later makes a cameo appearence in "Mr. Monk's 100th Case", interviewed about Monk while in prison.