Continuity: In the part where they're looking in the memories of the clone of Adam. They see two Adams but on the screen that's on the right it only shows one.

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."

Continuity: When Robert Duvall drops the folders on the floor in front of Drucker, notice they are all spread about in a mess. Then when Drucker goes to pick them up, they are all in a neat pile except for three of them.

Continuity: 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.

Revealing: 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.

Revealing: When Arnold Schwarzenegger is falling into the river next to the dam it is so obvious that the stunt man is being lowered at high speed on a cable. Not only does he not gain speed whilst falling, he falls at a constant speed and can be seen almost swaying in the wind.

Continuity: 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.

Continuity: 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.

Visible crew/equipment: At the end of the film when the 2nd Adam runs and jumps onto the 1st Adam who's hanging onto the ladder on the remote control helicopter you can see the 2nd Adam is a stunt double making the jump, most visibly by his hair and face.

Continuity: 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.

Continuity: 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.

Revealing: 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.

Continuity: 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.

Continuity: When Dr. Weir is about to show Adam the recording of Drucker's memory, we see him open the drive and put the disk in it; and then in the close-up shot, he does it again.

Revealing: 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.

Continuity: After Tony Goldwyn is done making his "saving the dying boy with the brain tumor" speech to the press he puts the microphone down on the podium and the next shot shows him turning and putting it down a second time.

Continuity: 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.

Continuity: 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.

Continuity: 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.

Continuity: When Adam enters the building with the girl's thumb, he gives the cooler to the security guard who begins to remove the tape, then the shot cuts to a view of Adam across the desk and the tape is back up, then when it goes back to the POV of Adam looking at the guard, the tape is back up.