This was the third Philo Vance detective film, and the only one to star Basil Rathbone. William Powell played Vance in the two previous films (1929 and 1930) and the two succeeding ones (1930 and 1933). It is fascinating to see the young Rathbone nine years before he made his first Sherlock Holmes film, 'The Hound of the Baskervilles' (1939). He is very much 'Sherlock before Sherlock'. There are two amazing character actors in this one, George F. Marion and Zelda Sears as the Drukkers, brother and sister. What faces! That was when people looked different, not the same as now when everyone is the same. The director makes the most of them, and they certainly add an eerie dimension to this story. A lot of people get killed in this tale, though of course we do not see the blood and gore because it is only 1930, and it is all we can do to hear the early sound sometimes. Cedric Gibbons as Art Director did some bold sets, with enormously high windows and huge rooms. The film is creaky in many ways, but it is a ripping yarn. Try and figure this one out! This is perhaps the cinema's earliest portrayal of a serial killer, which goes to prove that nothing is new. It is not a whodunnit, it is a whodunn'em.