Sherlock Holmes (Basil Rathbone) is on the trail of his arch enemy Moriarty (George Zucco) who is attempting to steal a crown jewel whilst diverting Holmes with a woman (Ida Lupino) giving him a false case. This is one of the series of Basil Rathbone / Nigel Bruce versions of the Sherlock Holmes stories. Ida Lupino is good as the woman who may be honest ot not.