The Lodger is Hitchcock's first thriller.

           London is beset by a series of Jack-the-Ripper-style murders.  The perpetrator calls himself "the Avenger" and has a penchant for  golden-curled girls.

          With the crime spree ongoing a lodger (Ivor Novello) rents a room in the Bunting family home.  He is a quiet man whose behavior is unusual.  (Novello's over-acting accounts for some of this).  He requests that the paintings of golden-haired girls be removed from his room;  they get on his nerves.  He keeps odd hours.  He paces endlessly back and forth.  Sometimes he slips out quietly in the dead of night.

          Mrs. Bunting (Marie Ault) notices that her lodger's most recent nocturnal excursion coincides with the latest Avenger killing.  Worse, her daughter, Daisy, (an actress known professionally as "June") appears to have fallen for this mysterious man.  And Daisy is a golden-haired girl.

          Daisy's affection for the lodger not only worries Mrs. Bunting, it absolutely enrages the girl's fiancé, Joe (Malcolm Keen).  Oh, and Joe just happens to be a police detective recently assigned to the Avenger case.  Jealousy combines with suspicion and Joe obtains a warrant for the lodger's arrest. 

           Police arrive at the Bunting home and arrest the lodger.  He escapes, still handcuffed.  Though innocent--of being the Avenger, at least--he is tracked down by an angry mob and nearly torn to pieces.

          The real Avenger is caught, clearing the lodger.  He and Daisy live happily-ever-after, as producer Michael Balcon demanded of a reluctant Hitchcock, who wanted the lodger to indeed be the Avenger.

          The following quotation is from Donald Spoto's The Art of Alfred Hitchcock: Fifty Years of His Motion Pictures:

"The Lodger is in every way a remarkable achievement, and it justified Michael Balcon's continuing confidence in Alfred Hitchcock's talent. Witty, visually inventive, genuinely disturbing despite its conventions, understated and economical (especially in its use of dialogue intertitles), it withstands multiple viewings and is virtually a textbook for Hitchcock's later work. There is, most of all, his favorite theme: an innocent man wrongly accused of a crime."