The Cheap Detective (1978)

Basically a comedy mash-up of Casablanca and '40s detective movies (Spade/Marlowe), and it mostly works. It's extremely silly and comically sexist and everyone dives in with gusto. 

That said, the script is about on par with the kinds of parodies we created in high school. It adheres to recognizable plot beats while replacing absolutely anything serious with the ridiculous and -- when in doubt -- leaning hard on the broadest of stereotypes.

B-