Continuity mistake: When Harpo is playing Russian Roulette, one of the villains claims that the gun has "four bullets" in it. One shot is fired at Harpo, and four by him, totaling five shots.
Continuity mistake: In the film's final scenes at the fuel storage facility, full sunlight is streaming through the overhead rafters. Moments later, it's completely dark and the plant's floodlights are all turned on. A few shots further on, the lights are off and it's daylight again.
Continuity mistake: Mrs Waggett brings in a tray with cups of tea on it while her husband is on the phone, reporting the sinking of a ship that contained hundreds of bottles of whisky. Mrs Waggett puts the tray on the left side of the screen, then, taking two cups with her, moves to the right of screen and that's where she stays when her husband finishes talking on the phone and, amazingly, the tray that was on the left side is now in her hands, without her moving to the left side to collect it.