Continuity mistake: Andy is discovered missing. While the warden is walking to Andy's cell, he tells the guard to question "him", meaning the Morgan Freeman character. He points to Freeman with his left hand but when the scene changes its point of view he is pointing with his right hand. (01:45:45)
Visible crew/equipment: Towards the end of the film you see the long haired baddie grab Milo by the hind legs (just before Milo puts the mask on). As Milo starts to change you can just about see the baddie who is holding his legs, except he is now a different person with brown curly hair, nobody who is seen prior or following this shot. Presumably he is the dog trainer. (01:23:15)
Continuity mistake: When John Travolta and Samuel L. Jackson are fired at in the apartment, the bullet holes are already in the wall before the gun is fired.
Continuity mistake: After Inspector Todd is shot, Axel chases after De Wald and fires at the truck. When the guy at the back of the truck is shooting at Axel, we see multiple bullet holes near the truck's back right window, but in his close-ups the bullet holes are gone. The window frame's scratched paint differs as well in the close-ups. We know it's the same window because we also see him in the shot of the truck's interior.
Visible crew/equipment: When the prams roll down the stairs you can see the ignition pipes that shoots out the babies. Clearly visible in the first pram. You also see some sort of ignition smoke from one of the prams after the baby has been "shot" out. (00:02:55)
Continuity mistake: When Mathilda spends her first night at Leon's apartment, Leon places a messily folded blanket on her in one shot. The camera then goes to a different shot of Leon, and then back to the original. However, we can now see that the blanket is mostly unfolded and placed neatly on Mathilda. ..... (and little pink doll she is holding changes position). (00:37:15)
Continuity mistake: When the cops first pull up beside the BMW and Jack pulls a gun out to shoot the cop with the shotgun, he hits a bump and blows the cop car's tire, causing it to flip. They show it flip behind the BMW, but the other 2 cop cars (on the passenger side and behind the BMW) have disappeared. (00:27:25)
Revealing mistake: When Draven sends T-bird to his death in his car, the real Ford Thunderbird is replaced by a fake mockup using a flimsy one-piece fiberglass body mounted on a pair of straight axles. When it explodes, the body lifts off in one piece, warping wildly while the front axle simply falls away. No proper car components like engine, transmission, suspension and so on, are seen anywhere, though they should be. (00:57:05)
Continuity mistake: During the car chase scene near the end of the movie when Connors jumps on to the black car the windshield is only slightly lowered. Later during the chase the gap is much bigger and when we see Callahan struggling in the back seat it's lowered all the way down. Also, Connors grip on the car keeps changing between closeups and far off shots.