Arsenic and Old Lace
Mortimer Brewster, a newspaper drama critic, playwright and author known for his diatribes against marriage, suddenly falls in love and gets married; but when he makes a quick trip home to tell his two maiden aunts, he finds out his aunts' hobby - killing lonely old men and burying them in the cellar!
A police detective falls in love with the woman whose murder he's investigating.
A rich woman and a calculating insurance agent plot to kill her unsuspecting husband after he signs a double indemnity policy. Against a backdrop of distinctly Californian settings, the partners in crime plan the perfect murder to collect the insurance, which pays double if the death is accidental.