Continuity mistake: Ray Cutler decides they should leave the Rainbow Cabins and picks up one of two stacks of books on a table to the right of the front door as he talks to Polly. No one goes near this spot but earlier in the scene there was only one stack of books along with a pocketbook (which is now on the floor) on the table. (00:49:45)????
Continuity mistake: In the first scene of the movie Marilyn is in bed smoking a cigarette and the shadow of the light coming through the Venetian blinds goes across the sheets from left to right. She hears George coming into the room, puts out the cigarette and in the next shot the shadow from the blinds has been rotated 90 degrees and is now extending from the foot of the bed to the head board. (00:03:20)????
Visible crew/equipment: After his supposed death we see George Loomis back at the Rainbow Cabins and he's standing by the garbage cans in the back of cabin B. We see him through a window and if you look closely a crew member's thumb can be seen on the window at the beginning of the shot. (00:46:35)????
Factual error: Marilyn and the Cutler's follow Inspector Starkey down to the bottom of The Scenic Tunnel Trip to identify George's shoes and when they come up Marilyn hears the song "Kiss" chiming from the bell tower. This is an obvious mistake as the shot of the bell tower that we see here is taken from the American side of the falls and The Scenic Tunnel Trip is on the Canadian side of the falls. (00:39:55)????
Continuity mistake: George Loomis goes over to the front door and shuts the light so that Polly Cutler can see the falls in the dark. The blinds on the left of the door are half open but when we see them again later in the scene, they're fully open even though no one has gone near them. (00:24:05)????