Continuity mistake: When Russ is lying down on the honeymoon bed you see him lying on his stomach. When the shot changes he is lying on his side with his legs crossed. (00:53:40)
Continuity mistake: When Bailey has parked and looks at the bag the tag on it change position between the shots. (00:02:20)
Continuity mistake: When David discovers Jade's dead uncle in the van, he grabs the uncle's glock pistol and actually cocks it twice before running out to the truck splatter scene.
Continuity mistake: When we see Tiffany walking away after killing Bailey, she is carrying the bag in her left hand. When it cuts we see her walking with the bag in her right hand and then she switches it over to her left hand again. (00:04:05)
Factual error: When Chucky blows up the cop car with a flaming rag in the gas tank, he is shown opening the fuel cap in the side of the car. The car in question is a Chevy Caprice, the fuel cap is located behind the rear licence plate.
Continuity mistake: When Tiffany files her nail after killing Bailey her hand change position between the shots. (00:03:25)
Continuity mistake: When Warren gets nailed, his face is contorted in a certain way. When the kids are leaving his house, his face is shown again and the contortion is very different. (00:41:15)
Continuity mistake: When Tiffany puts the doll dressed like a bride in the cage with Chucky, she throws a handful of rice in Chucky's face and most of it falls off, but the next time we see Chucky a lot of rice is sticking on his face. (00:27:05)
Plot hole: In this film Chucky says they need the heart of dumbbells to transfer their souls into human body. If he knew this why did he even attempt it in the first 3 movies? And he never uses it in the next 3 movies, including "Cult of Chucky," where he is successful at the transfer. (Side Note: The series writer has admitted that this was a ret-con added to the film in order to justify the road-trip. So, while still a mistake, it was purposely done).
Suggested correction: The amulet is necessary to amplify power in order to transfer multiple souls at a time - it's only used in Bride with two souls and Seed with three or four.
Continuity mistake: In the last movie, half of Chucky's face was sliced off by the giant scythe in the tunnel at the carnival, but in this movie, after being repaired, he seems to have a whole stitched up face, when half of it shouldn't be there.
Continuity mistake: In the previous 3 films Chucky has painted on eyebrows, in this one they're hair. Since this is the same body he had in part 3 they should be painted.
Other mistake: At the end, when Jade opens Chucky's coffin, there are several large rats inside, despite being sealed and buried under 6 feet of dirt for over ten years.
