Basil Rathbone makes a good Philo Vance in this murder mystery involving nursery rhymes. It's a forerunner of his great portrayal of Sherlock Holmes later in his career. He even uses his powers of observation to deduce that the sergeant (James Donlan) wrote a check that afternoon, soon has a date with a woman, etc., much the same way Holmes did, continually astounding Dr. Watson. But the comedy Donlan provides - and he's the only comic relief in the film - is on an infantile level. When he sees Rathbone for the first time, he says "I've solved this case, Mr. Vance. It's a murder." The script is really less than lacking in the humor department. On the other hand, all the other characters do not behave as stupid, and are believable in their roles. I loved the interesting faces and characterizations of George F. Marion and Charles Quartermaine. And there is one lovely photographed scene when Leila Hyams is sitting at a desk with a triple mirror when a sinister hand opens the door. You see her terrified face from four different angles at once, and it's a stunning effect.
This is the type of mystery that is virtually impossible to figure out. You have to go with the flow and watch the events unfold until the end when they are explained. There are lots of red herrings along the way, so I found myself switching from one suspect to another as the probable murderer. It was fun.