After Chucky is set alight, as he knocks down the fireplace guard you can see both his shoes have come off. In the following shots as he climbs across the sofa, his shoes are back on.
When the Good Guys Doll advert is playing on the Barclays' TV, in wide shots there is a box on top of the TV, yet in closeups of the TV the top of the TV has nothing on it.
When Norris chases Charles Lee Ray at the start of the film, he removes his gloves twice in the toy store.
When detective Norris is driving and Chucky is trying to stab him through the car seat, Norris clearly puts his feet up on the dash in the in-car view. But there are no feet on the dash on the outside view of the car. Also, when Norris does the 360 in the car, you can clearly see the driver is wearing a beanie, but Norris had nothing on his head.
The bite mark on Karen's arm changes positions and then mysteriously vanishes towards the end of the movie.
Eddie Caputo's shack fills with gas within roughly two minutes when it should take a lot longer to do so.
After Jack Santos Mike's detective partner phones for an ambulance he orders one right away. In reality it would take at least a few seconds to get an answer on the phone. Plus Jack should had been asked a number of questions about Mike's knife wound.
When Detective Norris asks Jack Santos if he's seen Chucky anywhere, he says "Who's Chucky?" and confusedly, "Why would I know anything about a doll?" Yet earlier at the station house, he was asking Andy "So why did Chucky want to see Eddie?" indicating Andy had told him pretty much everything. However, Jack is simply incredulous that Mike is asking him about a doll.
Somehow Andy was able to skip school and travels on a train free of charge. A lot of adults should have assumed Andy was supposed to be in school and there should had been a conductor on the train to charge Andy fares. However, Andy is shown whispering with Chucky a few times during this collection of scenes, and Chucky could have been instructing him in how to avoid being questioned during their trip, and he could have also instructed Andy to take the necessary amount of money from Karen to cover the train fare.
Charles Lee Ray's hands are covered in blood when he opens the Good Guy doll box and transfers his soul. Yet, there are no bloodstains on the box or doll when Karen buys it. However, the peddler could have simply cleaned the blood off the doll to avoid suspicion and make it easier to sell.
When Chucky first leaves the lift near Andy's apartment he seems to be heading for the door but a few scenes later he is seen coming down the chimney but there is no way Chucky could have done that inside the building. He would had to go back outside and climb the building to get to the roof. However, the audience isn't shown events in real time, and it seems that once Chucky got to the door it was already locked, then he climbed up to the roof.
When Mike is in the car being attacked by Chucky, after he hits a metal can and makes sparks, he swerves violently in the road, and on the road you can see several pairs of dark skid marks in the exact same place as he swerves, obviously from previous takes.
When Karen has Chucky barricaded in the fireplace, the arm that's moving Chucky is visible.
When Karen & Andy set fire to Chucky, he emerges from the fireplace still on fire and in a frenzy. He clearly sets fire to at least two pieces of furniture in the room, yet no one even tries to extinguish them. Nor does the fire appear to worsen.
When Chucky follows Andy home and drops from the chimney and kicks the cover off, it's obvious that this isn't Chucky, but it's a real person dressed as Chucky.
When Andy is hit by the baseball bat by Chucky you can see that the bat doesn't make contact.
Chucky could stab the guy in the car through the air but instead tries a harder way by stabbing him through the seat.
For some reason Karen was not informed Andy was not in school until the police call her after Eddie's home blows up.
At the start of the movie when the young boy opens the curtains its broad daylight at 6.30am. Yet at the time of the year that the movie is set in the winter it would be dark at 6.30am or at best heavy dusk.
When Andy jumps on Karen's bed, he shouts "Wake up, Mommy, Wake up." but his mouth doesn't move.
When Charles Lee Ray is about to Transfer his soul in the doll. He falls on the stack of dolls, grabs one smiling and unboxes it. Yet both of his hands are soaked in blood while he does so because of the fact he has been mortally wounded. Yet no matter how much he touches and manipulates the box no blood goes on the box. Revealing its dry paint on it.
Andy when he is told to go to bed by Karen turns his head around towards Mike Norris just before Norris mentions the boy's name.
When Chucky reveals himself to Cathrine Hicks and starts struggling in her arms, he is supported by a puppeteer hiding below the frame and not really hanging from Cathrine's arms.
When Chucky is trying to get out of the fireplace, a hand is visible pushing him into the fire screen.
When Andy is leaving school with Chucky you can see the reflection of the crew in the windows
Huge film light visible in the sky just before the car flips during the car chase.
Stunt driver clearly visible during the car chase.
Near the end of the movie, Chucky stabs the cop, Mike Norris, in the leg, and he falls and remains in the bedroom. Shortly after this, Chucky is shot several times by Karen, and his body parts are severed. This occurs in the living room and hallway. Mike Norris, still on the floor in the bedroom tells the backup cop who then arrives that Chuckie was shot and that his body is in pieces all over the place and to not touch any of them. It is impossible for Norris to know or to have seen any of this, as he was in the other room the entire time.
Chucky mispronounces the French words of the voodoo chant. Instead of saying "Pouvoir des morts" (power of the dead), he says "poivre de le morte" (pepper of the dead) with quite a few spelling mistakes.
Karen arrives at the police station to find that the officers have been interrogating her son. While some police are not above such a tactic, minors can only be properly interviewed with a parent or other adult advocate present. Failure to do so could render any evidence inadmissible.
Detective Norris is suspicious of Andy's role in Maggie's death due to finding footprints in the flour. However, it never occurs to him that the footprints are much smaller than even a young boy like Andy would have.
Karen tells the peddler that she had bought the Chucky doll from him the day before when in actuality she bought it several days ago.
Karen finds out that Andy skipped school when she arrives at the police station. Schools routinely call home when a child is absent, and someone surely would have seen Andy before he left.