Revealing mistake: When John Garfield is trying to stop Lana Turner from calling the District Attorney, Garfield holds the receiver up in the air off the hook. Then the phone rings. But a phone cannot ring when it is off the hook.
Revealing mistake: When the camera is tracking in to Peter Lorre whistling in the cafe, part of the screen gets noticeably darker because the camera is blocking one of the lights. This happens in other scenes, noticeably, when the camera makes shadows.
Revealing mistake: In Art Huck's living room before Pat Clark throws water into Marlowe's face, Lauren Bacall's eyes are closed in anticipation of being splattered (1945 Version on DVD). (01:41:30)
Revealing mistake: When CG and IB are on the plane, watch the scenery in the window. It appears to be going in reverse.
Revealing mistake: When a car drives by a store front and two hand grenades are thrown at it, the hand grenades bounce back into the street before the store blows up.
Revealing mistake: When Ballin's plane flies and finally crashes, it becomes obvious that the horizon is a still image with the film of the explosion superimposed directly onto it.
Revealing mistake: In the scene where the two gangsters take the dead Deputy Sawyer's body out to sea to dispose of it, as the actor is being pushed overboard, he tucks his arms into his chest, as if to prepare for the plunge.
Revealing mistake: When Joan Crawford shoots van Heflin, he reacts as if he was shot before the shot is fired.
Revealing mistake: The cake Mildred lifts is obviously a solid prop as the "frosting" does not smear her dress when she holds it close to her body.
Revealing mistake: In the final scene where Miss O'Shaughnessy is in the elevator with the detective, the door closes and the elevator starts to 'descend', indicated by dark glass going down, supposedly because the lighted elevator is passing beyond the view of the exterior door. But if you look, you can still see the silhouette of Miss O'Shaughnessy behind the glass, not moving. It is just a piece of wood or something being lowered behind the glass to simulate the elevator going down.
Revealing mistake: During the outdoor party at the Rainbow Cabins Marilyn asks the DJ to play "Kiss" in order to drive her husband George nuts, and after a couple of minutes he comes out and smashes the record. As he walks back to cabin B it's obvious this is a set as there's nothing inside the room except a blank wall. (00:20:15)
Revealing mistake: When our lead villain fires his shotgun at the cops behind the pipes, it lands in an almost perfectly square pattern instead of a more natural circle. The impacts look more like gaping exit wounds than where landed tiny pellets. The spread is also way too dense to miss the gaps that leave the cops exposed. (01:45:50)
Revealing mistake: Several pieces of furniture, including a large sofa, fall over before the suitcase bomb actually explodes.