"The Mystery of M. Felix" by B. L. Farjeon is a detective novel written during the late 19th century. The story unfolds in a snowstorm in London, centering around a mysterious character known as M. Felix, with a setting that combines elements of urban life and suspense. The narrative introduces Constable Wigg and his comrade, Constable Nightingale, who find themselves embroiled in the enigma surrounding Felix shortly after a cry for help is heard late at night. At the start of the novel, a restless constable on his beat hears a cry for help amid a severe storm, prompting concern and suspicion about M. Felix, a peculiar lodger living in a nearby house. Meanwhile, the housekeeper, Mrs. Middlemore, goes out for her regular supper beer and returns to find the street door open and a strange man escaping. This incident leads to a chain of events involving the constables investigating the situation inside, where they encounter ominous signs, including bloodstains and a locked door with no response from Felix. The urgency builds as the constables, Mrs. Middlemore, and a local doctor converge to uncover the truth about the mysterious happenings surrounding M. Felix and the implications of his possible absence or misfortune. (This is an automatically generated summary.)