Visible crew/equipment: During the montage of the kid, there is a shot looking in from the front of the car (featuring Dick Tracy and his girlfriend, with the kid in the middle) where the back window is just a blue screen, and the black stage curtains (behind the car) are visible at the top edges of the screen. (00:26:30)
Revealing mistake: In the shootout of the escaping cars, inside the second car, you can see roll bars in place for when the car rolls over and hits the parked yellow car.
Continuity mistake: Big Boy tries to bribe Dick Tracy in the basement of Tess' apartment. He drops two wads of loose bills on the table in front of Tracy. Cut to Tracy asking Big Boy if he is "gonna put all that money down". When the camera angle cuts back to Big Boy the loose money has disappeared and Big Boy drops wads of bundled money on the table. Cut back to Tracy refusing the bribe and he is gathering loose bills off the table to throw at Big Boy.