Help! Need name of old movie?

Can't remember much, but I know I really liked the movie. Its about a young innocent school teacher and she takes a job at a resturante at night. I think its a club too. Not sure. Anyways she bickers with the owner(I think) who is the scoundral type. She's engaged to some nice I guy. In the end she falls in love with the scoundral. Night might be in the title not sure once again. Its a black n white film. Older. Leading stars. It was on TCM a long time ago. Thats when I saw it. THANKS!!!