The movie is a remake of 20th Century Fox's previous film, The Lodger (1944), starring Laird Cregar as Slade. It was released under Fox's Panoramic Productions label. Barré Lyndon's screenplay for the earlier film was updated for the remake by Robert Presnell Jr., and Hugo Friedhofer's music score from the earlier film is also reused. The movie was shot on the same sets, and reuses footage from the earlier film of the police pursuing Jack the Ripper through the streets and over the rooftops of London.
The sixth and last victim of the Ripper in the film is Irish immigrant Mary Lenihan, who is killed in her one room flat. Her dying screams alert nearby constables who narrowly miss catching the serial killer. In reality, the last of the Ripper's five, not six, canonical victims was Irish immigrant Mary Kelly, killed and disemboweled in her one room flat, the only one of the victims killed indoors. Kelly's screams, if any, went unheard, and the Ripper mutilated her at his leisure throughout the night. The ghastly sight was not discovered until the morning when a rent collector saw the ghastly scene through her window at 10:45 a.m.
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duped from second- or third-generation (or more) copies of the film.