Revealing: In the shot where we see all the terrorists (except Karl and Theo, who are upstairs) walking into the building from downstairs, they are about to walk through a doorway when the camera cuts out. Watch the terrorist on the left (he's the one who guards the door) - before the camera cuts out he realises he's about to hit the doorframe very hard. Reminiscent of the Stormtrooper in Star Wars.

Revealing: When the boss discovers the first bad guy lying dead in the lift ("Now I have a gun - HO HO HO!") and slaps him over the cheek, the corpse is moving its head before it is hit (watch carefully!) He also blinks.

Continuity: When the terrorists launch the rocket at the RV, they break the same window of the building twice.

Continuity: When Bruce is looking on the touch-screen computer to find out where his wife is, he touches the name GENNARO, but when it changes colour it also corrects the spelling of his wife's name to GENNERO.

Revealing: Bruce Willis wore fake feet during the movie to protect his own while shooting the film. They were like boots that slipped on over his. At the part where the FBI guy shoots at him from the helicopter and Bruce jumps to a lower level of the roof, you can see the tops of the fake feet that aren't tight around his ankles.

Continuity: When John and the terrorist fall down the stairs together, you can hear the yell of the terrorist signifying his death. Leaving the fact that dead men tend not to yell out alone, you can see the terrorist's corpse is still breathing.