I say "attempts" because most of the comedy just falls flat. This could have been a great little thriller if Broderick Crawford and Hugh Herbert's bumbling around in the dark could have been omitted. Instead, this film comes across more inane than sinister.
I give it 6/10 because the mystery is good enough and the atmosphere is pure Universal horror. The background of the story is that a wealthy elderly lady has provided her estate as a haven for homeless cats, complete with creepy crypt and crematorium for them when they die. She has just dodged another bout with death through illness when she decides to read her will to her greedy relatives ahead of time. Shortly afterwards the elderly woman dies mysteriously, followed by the discovery of an addendum to the will, followed by the mysterious deaths of other members of the household, all during the period of one dark and stormy night. For some reason Universal figured the presence of an investigating protagonist would not be enough for this one - that injecting some bumbling good guys in the spirit of Abbott and Costello would be a good idea, but they (Broderick Crawford and Hugh Herbert) just distract the viewer from the mystery aspect with their lame attempts at humor.
The sad part of this film is how little Bela Lugosi is given to do. At this point in his career he is pretty much relegated to walking around and looking creepy.