There are a number of continuity errors during Dr. Lombardi's first performance at Tim Chappel's home: 1) when the dancer finishes, Ted and Dorothy shift to her position in the following shot, 2) during their conversation, the patio curtains are drawn wider in long shots than in closer shots, 3) when Lt. James finishes talking to Ted and leaves the frame, he is gone from the following wide shot, 4) Ted takes his seat twice, 5) the cutaways to Lt. James show him in a lit room when in all other shots the lights are dim, and 6) when Dr. Lombardi announces the creature's appearance, Lt. James mounts the stage from the right, but it is clear from preceding shots that he was nowhere in that vicinity.
Dr. Lombardi gives his first demonstration at the Chappel Home at 34 minutes and again at 1 hour 7 min. By watching the women's dress, it appears to be the same audience who were, for the most part, re-seated in different positions for the later demonstration. The most obvious example was the woman who remained in the first row for both demonstrations.
At the end of the movie, Tom Conway is "chased" by the She-Creature. It looks
like he is using a standard .38 caliber, six shot pistol. He fires the
weapon seven times without reloading.
When Dr. Lombardi pulls down the sofa at the beach house, revealing a man's body, it falls onto the sofa with the left arm squarely at his side. In the next shot, the arm is draped over the sofa's edge.
When he first goes into the house at the start, Ted has his pipe in his mouth, but when he finds the murder victims in the next shot, it has vanished.
When King departs from the seance after growling at Dr. Lombardi, he is wearing a collar with a hook and leash to provide his cue.
The newspapers that are shown do not have reporter or author names for the articles.
At 1 hour 12 min a series of monster foot prints appear in the sand, one print is going the wrong way.
The wires attached to Professor Anderson's glasses can be seen when they are lifted off him.
When Dr. Erickson first addresses Andrea in her hypnotized state as Elizabeth Ann Weatherby, he calls her "Andrea" but Elizabeth answers normally. If he thought she was faking and was trying to trip her up, the script makes no reference to this.