Here is a first-hand description of some of the doings in the slimy, mysterious places of the largest city in England. Here the detectives of Scotland Yard know of many strange things and see the results of the workings of such evil minds as Dr. Fu Manchu. The author is one of the few men who has penetrated the secrets of the Limehouse underworld sufficiently to enable him to write about them authentically and interestingly. Here are sudden deaths in peculiar ways, mysterious disappearances and all sorts of crimes --- where human life is valued none too highly.