Revealing mistake: When the group is being attacked in dining hall B, they are trying to get the doors open. J.D. is firing at two zombies and turns away to open the doors himself because Kaplan keeps forgetting the code. If you look closely, one of the zombies reacts a second late from being shot down. (00:44:40)
Revealing mistake: When the team leader is opening the door to the Red Queen chamber, he clips an electronic device to the door to hack the code. The device is actually a blood glucose monitor as used by diabetics - an Accu-Chek, I think. (00:31:05)
Revealing mistake: On the DVD commentary, the director says that he only had a handful of the experiment cubes in Dining Hall B and used cardboard cutouts for all the others. This is most obvious when Rain is walking through the hall alone to check on the first zombie: the cubes in the distance don't match the rigid rows of the ones in the foreground. (00:38:20)
Revealing mistake: When the survivors first get into the sewers, the camera goes forward on the dolly as they come around the corner. Until the camera gets its close up of Alice, everyone's hugging the wall to get out of the camera's way. (01:01:00)
Revealing mistake: In the scene where Milla Jovovich shoots the dogs with the 9mm Beretta she obtained from the dead security guard, a closeup of the gun is shown. Watch the cycling of the slide and you will notice that the ends of the bullets are crimped, indicating the use of blanks. (00:49:55)
Revealing mistake: When Alice hits the zombie Spence in the head, she misses Spence by a lot. (01:18:50)
Revealing mistake: When Alice hits the first person in a biohazard suit, the padding is visible on the chest section. (01:25:40)
Revealing mistake: When Kaplan is trying to turn off the lasers, take note of his keyboard. His fingers aren't touching the keys. (00:31:20)
Revealing mistake: The Red Queen tries to goad Alice into killing Rain in the laboratory, with the Licker pounding against the glass outside. Just after they escape the room, the Licker breaks in. Watch its jump very carefully. you can see the exact invisible "line" where the Licker stops being a guy in a suit and becomes computer generated. It even changes colour. (01:20:45)
Revealing mistake: As the team gets off the subway and heads for the door into the Hive, the Red Queen's POV shows a nifty infrared display in the lower left corner that marks their locations - it obviously matches up to the ones on screen. But the dots are static, while the people are moving. (00:19:20)
Revealing mistake: When the Red Queen scans the doctors in the lab, it displays "Dr. Anna Bolt." This is the name of the actress, not the character. (00:05:10)
Chosen answer: The winner was the English girl playing the Red Queen.