Continuity mistake: When Lazlo says "If she moves put your cane in her eye" to his mother, Cynthia is sitting with her hands down. When it cuts her hands are under her chin. (01:05:45)
Continuity mistake: In a late scene in the movie when Jill St. Claire angrily drives away after arguing with her husband in the parking lot of the motel, the side shot of Jimmy the Tulip shows his golden lucky charm dangling from his neck outside his white t-shirt. In the next frontal shot when he turns around to talk to Oz, the necklace is now tucked back inside his t-shirt. (01:08:10)
Continuity mistake: When Jill finds the half dollar bill, the bill suddenly flips in her hands during the shots. (01:09:20)
Audio problem: Even when Oz has hung up the phone with Lazlo you can still hear Lazlo saying "Can you hear me?". (01:10:00)
Continuity mistake: Near the end, when Oz is going off on his secretary, he mentions that Jimmy fed him chicken, but it was lobster. (01:12:30)
Continuity mistake: After Jules has chloroformed Jimmy she pulls up her gun while holding the cloth with chloroform. The way she holds the gun and the cloth changes during the shots. (01:15:15)
Continuity mistake: When Jimmy gets to Oz's office, Oz is leaning on a rack with two jackets. It falls down and Oz picks it up again, but now only one jacket is on the rack. When it cuts, suddenly both jackets are hanging on it. (01:17:35)
Continuity mistake: Towards the end of the movie when Amanda Peet is holding half of a dollar bill and Howard Deutch is holding the other half, the position of the ripped dollar in Amanda Peet's hand changes between shots. (01:21:30)
Continuity mistake: Near the end of the movie, when everyone has been "captured", Jill rips the crucifix and chain off of Jimmy's neck and throws it at Cynthia. In his next closeup, you can still see the chain on Bruce's neck. (01:22:30)
Continuity mistake: When Jill is pointing her gun at Jimmy, she changes between gripping the gun with both hands and with one hand. This happens multiple times during the scene. (01:26:25)
Continuity mistake: After Jill has shot Jimmy she grabs her face crying. When it cuts her hands aren't on her face. (01:28:15)
Continuity mistake: At the end when they are driving away in the car and Oz says "This is too much. It's great, but too much." Jimmy is patting him on his shoulders. When it cuts Jimmy's hand is gone from his shoulders. (01:29:35)
Continuity mistake: When Jill is standing over Lazlo ready to shoot him, Jimmy tosses her a rope, which she quickly drops on the floor. In the next shot the rope is back in her hand. (01:31:00)
Continuity mistake: When Cynthia is driving down the road talking to Jimmy on her cell, she hangs up twice at the end of the conversation.
Continuity mistake: Early in the movie, when Jill St. Claire tip-toes into the house while Jimmy the Tulip is busy with household chores, she invariably gets caught by the new family man anyway and eventually takes the argument with him upstairs to the bedroom. Carrying on the shouting match with her husband while getting change in front of the closet, a pair of shiny silver handcuffs (most likely the kinky kind - what business could a hitman possibly have with handcuffs?) can be seen hanging behind her head. By the time the outer layer of her clothing is stripped, the handcuffs disappear.
Continuity mistake: The first time Bruce Willis talks to Matthew Perry on the phone Bruce holds the phone in his right hand. Bruce's watch changes positions, well below that bump/bone below the wrist to above the bump/bone and then below again. Bruce never lowers his arm, or the phone, to cause the watch to move.
Continuity mistake: The damage done to the rental car changes from the time Jill leaves the hotel parking lot (when she's mad at Jimmy) and when she is shown driving it on the street.
Continuity mistake: When Jill and Jimmy are arguing at the motel, Oz tells Strabo that Jimmy killed 21 people. Later at the bar when Jimmy is very drunk, he tells Oz that he has killed 21 people. Oz corrects him and says, "22 people", and Jimmy says, "Who'd I forget". Oz replies with "Frankie Figgs". Apparently Oz had forgotten that information as well when he was bragging to Strabo earlier. (Also, why would Oz know who Jimmy had forgotten?).
Plot hole: Jimmy tells Oz to "pull out the wires" from under the dashboard to hotwire the car. Firstly, car manufacturers (including Buick) don't have the ignition wiring that is easily accessible, and secondly, assuming the car didn't have an immobiliser, at what point was the steering lock broken? Er, it wasn't.
Plot hole: Why do they need both halves of the torn dollar bill to access the bank account? All American bills have a copy of the serial number on each half, no matter which way you tear it, as long as it is in roughly equal parts (top and bottom or left and right).