Goofs

During the climactic scenes at the shed, the blood stains on the lapel of Frank's jacket disappear and reappear.

When Candy is sent away from preschool by "the creatures", she is wearing her red snowsuit. However, when Frank drops by their home, desperately searching for his daughter, the red snowsuit is hanging on the cloak hook at the front door. Then again, a few moments later, Candy is wearing it walking down the street with two of "the creatures".

Nearing the end when Nola (S. Eggar) is breaking open her latest brood sac with her mouth, the first blood spatter onto her face does not match with that shown in next scenes.

In the watching after his daughter (Candy) going into the school doorway scene, the other leaving woman (Mother?: in red coat) there is shown turning and leaving from the shot: next shot from rear of (Candy's father) Frank (A. Hindle) at distance looking on, shows the same person (Mother?) still dropping off her child and once again turning to leave.

After Dr. Raglan checks the work shed he pulls out a revolver and checks the cylinder before snapping it closed. There are no bullets in the cylinder.

Just after the first murder, the deformed/mutant child who committed it leaves very large, bloody handprints on the stair railing just near the dead body. These handprints are never mentioned again, in particular by the police, who insist later that they were "never looking for anything that small." It would have been impossible to miss these handprints at the crime scene, and such child-sized handprints would have certainly tipped off the police in a different direction upon discovery.