One Body Too Many (1944)

A fun comedy horror / mystery romp. An eccentric millionaire has died, his relatives (whom he mostly hated) gather to hear his will. However he has a final strange stipulation, unless he is buried in a glass dome he will have the terms of his will reversed so those who get a lot will get little and versa. A string of mysteries and intrigues begin...

Hapless insurance agent Albert (Jack Haley) is dragged into the intrigue by Jean Parker and ends up having to try and find out who is trying to steal the body, bury him underground and reverse the will...

An entertaining film full of dark house mystery tropes (hidden passages, stormy night, real eyes behind paintings et cetera). It even has Bela Lugosi in it as the somewhat creepy butler obsessed with making coffee.