While this film has no big names (in fact no names I have heard at all), it still manages to be a fun "old dark house" film with a clever plot and interesting characters. The story and plot revolve around radiation, which I found to be very appropriate and a bit novel for the 1940s.
I also have to call out the black servant, Woodrow, played by Willie Best. Best may not be a household name, but he had an incredible career (including such films as "High Sierra" and "Cabin in the Sky"). Maybe it is wrong of me to find humor in these "black servant" roles. Maybe they are racist. But Best does them well, making the characters he plays endearing and fun. I look forward to seeing his work.
I recommend this film. It is short, so you are not investing much time. And it is well-written and of above average quality. Definitely worth a peek.