The Great Radium Mystery
Also known as The Radium Mystery in the USA
B&W : Serial / 18 episodes
Directed by Robert B. Broadwell and Robert F. Hill
Cast: Eileen Sedgwick, Cleo Madison, Robert Reeves, Robert Kortman, Edward Brady, Jeff Osborne (Jeffrey Osborne), Robert Gray, Gordon McGregor, Fred Hamer
Pacific Producing Company production; distributed by The Universal Film Manufacturing Company, Incorporated. / Scenario by Frederick Burnett. / 18 episodes:  “The Mystic Stone,” released 13 October 1919. / Standard 35mm spherical 1.33:1 format.
Survival status: The film is presumed lost.
Current rights holder: Public domain.
Listing updated: 23 January 2004.
References: Lahue-Continued pp. 68, 193-194, 285; Stedman-Serials p. 47 : Website-IMDb; Website-SerSq.