Revealing mistake: During the bedroom scene with Felicity and Fat Bastard you can clearly see the air hose that fills his suit when he rolls over in the bed. (00:49:10)
Plot hole: Lucy jumps from the airliner and flies her hang-glider straight to Eduardo/El Macho's Cinco de Mayo party to find Gru. How did she know Gru would be there? He had no intention of going and only did so after he was pestered into it by the girls on the very night of the party, so he couldn't have told her himself. Shouldn't she have gone to his house instead? (01:09:50)
Continuity mistake: In the final battle, Wasp and Ant-Man are in the van trying to get the quantum tunnel operational. We cut back to the fight and we can see Ant-Man there too, fighting in his giant form. (02:22:20 - 02:23:00)
Revealing mistake: There are supposed to be two dead young Asian males sitting in the back of the car, but in this shot, it is so obvious that there are two dead 'dummies' riding in the back. Also, in the crash, a few seconds later, very blatant dummy heads are flying everywhere. (00:40:40)
Continuity mistake: The owner of the Cleveland Browns drives from NYC to the Teterboro Airport (12 miles from Midtown Manhattan), flies to Cleveland (450 air miles) and drives to the Browns facility (16 miles) in the time it takes the 2nd, 3rd, 4th and 5th picks in the 1st round of the NFL draft to be made.
Factual error: Listening to a radio broadcast, live, since no other indication is given, Joe Louis is completing the 12th round of a fight. This is December 6, 1941. Joe's last fight of 1941 occurred in September, his next fight was January 1942. (00:00:10)
Continuity mistake: When Brant kills Barry at the end of the movie, Brant lowers his gun after shooting him, but in the next shot he is pointing his gun at Barry. Also, the scene shows Brant holding a semi-automatic style handgun before shooting Barry, then when the scene pulls out it shows him holding a revolver, then shows him holding the semi-auto again.
Continuity mistake: When swimfan85 is trying to talk to Ben and he tells her he has homework to get done, she is talking with the nick name swimfan85 but when she signs off it says "swimfan has signed off." They forgot to add the 85.
Continuity mistake: In the first film, it is mentioned several times that Kevin is 8 years old. However, in this film it is stated that he is 10. When his parents are in the Miami airport security office, they say that he was left alone last Christmas. That would make him 9. Both films take place the same days, from about three days before Christmas until Christmas morning, so even if Kevin is born around Christmas time this is still a mistake.
Continuity mistake: In the final scene where Roxie and Velma are dancing in the concert hall, Roxie is on the right and Velma is on the left. They then turn around, and from behind (same point of view as before) they're suddenly the other way around. (01:44:20)
Audio problem: In the scene after Reese Witherspoon and Luke Wilson are returning from questioning the ex-wife of the murder victim at a spa, they are driving up in Luke's car. You can clearly see, as they get closer to the camera, that what you hear Luke saying isn't what his lips are saying. It was a very obvious dub over...and a very bad one.
Continuity mistake: There is a scene where the Chipmunks and Chipettes are singing the song "Girls of Rock and Roll." In that scene, it shows the boys walking up the stairs together and from left to right the order is: Simon, Alvin & Theodore. The shot goes to the girls then back to the guys. The order of the guys has switched: (left to right) Theodore, Alvin & Simon.