Continuity mistake: When Nancy defuses the bomb, leaps into the air and falls down, her head is rested on her arm when she is lying on the floor (in the first scene). In the next scene, her hands are both together and her head is on the ground. (00:50:50)
Continuity mistake: When Nancy drew is talking to the guy about the records for adopted children the cake she gave him keeps appearing and disappearing off the napkin as the shot changes.
Other mistake: When Nancy finds the trapdoor from the attic, she goes down a ladder and gets onto the other floor. She walks a bit and goes down another ladder then looks up and Ned throws the flashlight straight down to her.
Deliberate mistake: In the facial morph, the faces don't come anywhere close. The face was morphed with no feature of either resembling the other. The only matching features were the hair and neck which were not touched by the morph. The midpoint of the shift wreaks of Photoshop-like effects (softening of the face alone). (00:41:50)
Continuity mistake: When Nancy's shoes are stolen, in the next scene she is wearing the same shoes that had been stolen, but in the end of the movie you can see her wearing them and the "stolen" shoes are lying on the thief's desk. (00:15:10)
