When Columbo is eating at the commissary and overhears the conversation between the two actresses, he puts ketchup on his food. But, when the camera switches to a two-shot of the actresses, the ketchup bottle is sitting on the counter in front of them. See more
[referring to the water bed
You know, I've never tried one of these. My wife, that's Mrs. Columbo, she tried to get me interested.
[after Columbo lies on the bed
Well, how do you like it?
Well, to tell you the truth, sir, it feels all swimmy. Makes me wonder what Mrs. Columbo had in mind.