In the beginning of the film, when Nick finishes talking with the hotel clerk, he sits in an armchair in the lobby smoking. The big pot ashtray is on the left of him. In the next scene, the ashtray is on his right. He goes for it to the left, surprisingly finding it on the right, so he drops his cigar on the floor.
On the window of his barber shop and in the note he receives in his hotel from his friends at home, Nick's last name is spelled "Venizelos"; but on his volunteer fireman's card (inspected when he enters the gambling den), it is spelled "Venezelos".
When Irene Graham sits down to talk to Nick, her legs are closed together in a parallel position and she wraps her arms around them. In the next immediate shot, her legs are now in different positions, and her arms are no longer wrapped around them.
When "drowning" girl is rescued, it's late at night when she's driven to Nick's home, but when they pull up in front of his house, it's broad daylight.