Continuity mistake: Dr. Marvin tries out his new improved magnetic interference unit and an alien craft is spotted flying around inside of the Belmont lab above their heads. Before the craft takes a dip down at them they're standing on the right of Dr. Marvin's magnetic device, but when we see them again they're standing on the left of his device. (00:50:20)????
Continuity mistake: Dr. Marvin walks in as Carol sleeps in their hotel room and then proceeds to call the aliens on his shortwave radio. By the time he walks out of the room to meet with them by the Chesapeake Bay the items on top of his dresser have moved, without anyone going near them. (00:31:10)????
Continuity mistake: Carol and Dr. Marvin are locked in the underground bunker at "Operation Sky Hook" as the power goes totally dead. Somehow in total darkness without any power we still hear the sound of the aliens speaking which is strange because if you look at the tape recorder it's not running at all. (00:24:40)????
Continuity mistake: Carol and Dr. Marvin are locked in an underground bunker at "Operation Sky Hook" and the doctor makes a tape recording of himself as the power goes out and the lights start to flicker. He says, "The batteries are failing, the recorder's not running up to speed" but if you look at the tape recorder it never slows down and keeps running at the same speed. (00:25:05)????
Continuity mistake: Dr. Marvin runs out of their hotel room and proceeds to his meeting with the aliens by the Chesapeake Bay. Carol calls Major Huglin in his room and we see that the filmmakers used the same room for both shots with items such as paintings, beds, lamps and water pitchers moved to different spots. (00:33:10)????