This is among the better entries in the comedy/mystery genre popular in the 1940s. No one liked the person murdered. Many people had reason to do him or her in. All are assembled in creepy surroundings.
Apart from a plot that's easy and logical, what sets this apart is Aline MacMahon. She plays a nurse who happens to be in the house and who helps the police solve the crime.
MacMahon was unique in Hollywood history. Though only in her thirties here, she was already playing an old maid. Yet she had an occasional fling at glamor roles. And she was an exceptionally good actress, with a haunting beauty.
Her rather heavy-lidded eyes seem to bore right through her co-players, here as elsewhere. ZaSu Pitts had a somewhat parallel career. But at least Erich Von Stroheim saw her as a beauty and a great actress.
Maybe MacMahon really couldn't have done it. But I think she had the potential for far greater roles than she was given. As strange as this probably sounds, I can see her, decades later, as the tragic Mary Tyrone in "Long Day's Journey Into Night." (She would surely have been better than Katharine Hepburn, an actress, I often liked, in that role.)