Continuity mistake: In the scene where the two guys are playing chess, the guy with the black hat knocks over the chess pieces after losing. He then starts scrambling up the pieces and leaving his hands near the chess board. When the shot changes to a wide shot of Monk walking away the guy suddenly has his hands on his head.
Continuity mistake: When Monk is lost in the street crowd after getting pushed into the subway car, his left shirt collar is sticking up over his coat. It's still up when he puts his hands to his head, but is tucked neatly back in in the next shot, though he still has both hands on his head. A few seconds later, it's the right collar flap that's sticking out instead.
Continuity mistake: There is a shot where Randy is trying to cross the police tape and an officer stops him, and he can be seen briefly arguing. However, when it cuts to the next shot, we see that argument happening again in the background, repeated. (00:07:20)