Continuity: When Monk spills the potted plant and grabs a vacuum cleaner from the hall, he's holding the handle with several large paper towels. When he plugs the vacuum in, he now has a wipe in his hand instead. When he's finished plugging in and turns around, the wipe has vanished and there's nothing in his hands or on the vacuum. But when we cut to a wider shot as he turns the vacuum on, the paper towels reappear on the handle. Submitted by Jean G

Deliberate "mistake": All the mail bombs are delivered in packages tied with knotted string. The USPO hasn't allowed string-tied packages since the mid-90s (they get caught in automated equipment), but since the knots were crucial to ID-ing the suspect in this episode, that fact had to be ignored. Submitted by Jean G