Directed by Frank Capra
Written by Julius J. Epstein and Philip G. Epstein
IMDB

Cary Grant plays an author and play critic who has made his name off of writing anti-marriage books. The film begins with him in line to get married. He and his new wife are on their way to Niagra Falls, but stop off at Grant's aunts' house. Grant's brother(?), Teddy, thinks he's Teddy Roosevelt, and his aunts are murderers. He tries to postpone his honeymoon so he can get Teddy committed. Things get really out of hand when Grant's long missing brother, Jonathan, comes back with his doctor to perform some surgery and bury a body in the basement.
Cary Grant is absolutely hilarious in this dark/slapstick comedy. He doesn't get a ton of screen time, but whenever he's onscreen he had me laughing hard with his off the wall antics. When he's offscreen the other actors are still funny, but they never match Grant's craziness. Really great movie.

10/10