The Phantom Ship (1935) stars Bela Lugosi (The Wolf Man, White Zombie, The Corpse Vanishes, Dracula, Mark of the Vampire). There are no supernatural elements here but plenty of murder mystery. I can't remember why I listed this with horror films. I think I'll take it off the horror movie list.
8/16/2008: sadly, I can no longer find this online.
10/1/2008: Ah! Here it is.
9/3/2009: Nope, gone again.
9/29/2012: It's back! via Youtube: