The scene in which Bigelow runs in panic through the streets after learning he has been poisoned was a stolen shot. The pedestrians had no idea a movie was being made and no warning that Edmond O'Brien would be plowing through them.
When Frank Bigelow registers at the Allison Hotel in Los Angeles, the name directly above is Russell Rouse, one of the writers. Also on the register is Ernest Laszlo, the director of photography and Marty Moss, the assistant director.
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.
Pamela Britton plays Paula Gibson, the insecure and pushy girlfriend of Frank Bigelow, played by Edmond O'Brien. In 1951 Britton would be cast as Marge Porter in TV's The Bigelow Theatre (1950), a series of teleplays, but which had nothing to do with the name of Edmond O'Brien's character in this film.