I like the Michael Shayne films, and this one from 1940 has humor, a decent mystery, and is generally fun.
Millionaire Hiram Brighton hires Michael Shayne (Lloyd Nolan) to watch his daughter Phyllis (Marjorie Weaver) - she's a compulsive gambler. In fact Shayne moves into the house, to no avail, because Phyllis escapes him.
Shayne fakes the murder of her gambler boyfriend to frighten her, but it doesn't come off, since upon his discovery, Shayne realizes he's been shot. Gun mix-ups, a frustrated and furious police chief (Donald McBride), and the casino owner's wife (Joan Valerie) are all present to mix things up.
The end of this film falls apart and gets a little confusing with people faling down stairs and coming out of closets, but in reality, the lively characters are what keep this film going.
Just about stealing the show is Phyllis' eccentric aunt (Elizabeth Patterson). She and the butler are mystery fanatics - she is a great follower of the "Baffle Book" and is always telling Shayne about different stories. She actually proves to be a great help to Shayne. Patterson is best remembered, of course, as Mrs. Trumble on I Love Lucy.
Enjoyable.