Continuity mistake: Near the end of the film, Adam and his clone make a jump for the helicopter to escape the explosion. In one scene, you'll see Sport Jacket Adam holding the ladder to the helicopter with Leather Jacket Adam holding onto the legs of the first Adam. After a cutaway scene, you'll see these two have switched places (Leather jacket on ladder, Sport jacket on bottom). The next time you see them, they're switched back in the correct order. (01:52:30)
Factual error: When Arnold is in the police station reporting that he has a clone and passes through a control room, one computer screen is flashing "OVERIDE." The correct spelling is "OVERRIDE." (00:38:05)
Continuity mistake: In the car chase early in the film, we see Adam drive the Cadillac down a flight of stairs. A shot from the front show the car going over the top of the stairs, and as it bounces the lights going out. By the time we see the car again, the lights are full on. (00:28:25)
Continuity mistake: Towards the end of the movie, in the scenes involving the dying Drucker (Tony Goldwyn) and his half-formed clone, blood on the dying Drucker keeps disappearing and reappearing. In one scene he is bleeding out his mouth and down the front of his throat. The camera cuts away and when it comes back his throat is clean. Yet in the next scene his throat is bloody again. (01:46:10)
Revealing mistake: In the parking garage shoot out Arnold shoots the leg off a bad guy. While the bad guy is writhing in pain on the ground you can see his leg tucked back. (00:59:50)
Continuity mistake: When Drucker jumps from the roof onto the glass at the end(to avoid the rotors of the Whisper Craft), the establishing shot shows him on the last panel of glass next to the wall. However when you see Drucker fall from the inside shot, he falls from the middle of the glass roof and no wall is seen anywhere near him. (01:51:50)
Revealing mistake: After Arnold Breaks Wiley's neck outside the police station and sets him down on the ground, in the next shot where they show Wiley on the ground you can blatantly see his stomach move from breathing, even though he's dead. (00:44:15)
Continuity mistake: When clone Adam is running towards the helicopter and gets shot in his left leg. The other Adam sends the helicopter away. When the helicopter comes back, clone Adam limps on his right leg. (01:50:40)
Continuity mistake: When Schwarzenegger returns to his company and removes the photo of him and his family from his locker he then looks in the mirror at his shaving cut, in doing so lifting his cheek right up to see the cut which is obviously under his chin. In all the other scenes however, the cut is clearly visible without having to pull or distort the face. (00:48:15)
Continuity mistake: When Talia is first killed, while in the Cadillac, the passenger door is blown off. When Adam drives through the water there's an inside shot of him and you can tell the door is back on for the scene. After going down the stairs there's the same inside the car shot of Adam and you can see the door is missing.
Continuity mistake: When Arnold is jumping out of his car when it is about to go off the side of the cliff, he would have to open the driver side door, and jump out that way. Still, when we see the car go through the air, into the water, the driver side door is closed. (00:29:45)
Continuity mistake: When Adam is in the police detention room, he props a chair under the doorknob to keep anyone from entering. The chair is propped with the seat up, but when the police break in and the chair flys away from the door, you can see that it had been positioned with the seat down. (00:43:05)
Revealing mistake: When Arnold is back at his partner's house and the guy comes in shooting, watch the 1st shot as Arnold dives out of the way. The film editor's timing is off because it appears that he's jumping into the gun shot. (00:56:25)
Continuity mistake: Near the end of the movie there's a scene where the lead antagonist meets his clone, the antagonist's sweater has a hole in it from where he was shot. The clone needs the antagonist's clothes and takes them from him, but the hole from the sweater is missing. In another scene, the hole is present. (01:45:40)
Continuity mistake: In the final shoot out on the roof there is a quick shot of Arnold firing a gun wearing the grey security outfit he stole from the guard earlier in the film. The only problem is at the time one Arnold is wearing his leather flight jacket and the other is still dressed in the sport coat outfit he wore to his daughter's school. This is obviously a shot from an earlier scene they used again later.