Goofs

Robin comes up to the door of her apartment with a bag of groceries, which includes two upside-down bunches of celery (root end up), and a square-shaped box of eggs. Then as the camera angle switches to show her coming through the door, the two bunches of celery have suddenly switched to right side up (leafy end up), and the square box of eggs has magically turned into a rectangular shaped box.

At about 21 minutes into the film David enters the apartment carrying a moving box full of Robin's shoes and one of them is sticking out of a corner of the box. David looks around a bit and then when he turns around that shoe is no longer sticking out of the box.

At about 1 hour into the film Hogan carries two grocery bags inside for Robin, sets them down and has a green sprig hanging from his mouth. He then sets the sprig on a fruit plate. They move to a shot of Robin and then back to Hogan where the sprig is now sitting on a different part of the plate. Then, moments later, he is suddenly holding a cigar that has been previously lit but is not emitting any smoke. This non-smoking cigar appears several times in later shots.

At about 1:13 into the film David finally kicks Hogan out of the apartment and appears to lock the bottom door lock, which is not a bolt-type. He would have needed a key for it but he was holding none.

At about 33 minutes into the film Hogan attempts to look into the apartment using a rake to hold a mirror. As he moves the mirror to a point where he supposedly sees what's going on inside, the reflection can be seen on the wall and therefore not visible to Hogan.

At about 59 minutes into the film Hogan is rowing a boat in front of David swimming in a pool. Boats are not allowed in swimming pools.

Shadow of crew member/equipment moving in scene where David hits Irene over head with vase.

At about 1:07 into the film David is opening the door for Robin and Hogan while carrying a lit cigarette. This is the only point in the film where he is shown smoking. Then later, with that same cigarette, he is shown taking a puff but it is not lit and no smoke is visible.