Arsenic and Old Lace explores the challenges of family, especially when your family happens to be insane. Cary Grant plays Mortimer Brewster, who discovers terrifying secrets about his sweet old aunts.

While Mortimer is visiting home before going on his honeymoon, he learns that his aunts have kindly been putting lonely men out of their misery for years. He cannot believe that these sweet old ladies could be serial killers, but he is forced to and wants to protect them anyway.

Then, Mortimer's long lost brother, Jonathan, returns home after a long absence. Jonathan is a cruel criminal, a killer with a record as good as his aunts' - almost. As Mortimer and his aunts try to outwit Jonathan, Mortimer becomes increasingly concerned about the insanity running rampant through his family. Mortimer finally defeats Jonathan and has his aunts and uncle committed to the insane asylum, right after...