The Valley of Vanishing Men

The Valley of Vanishing Men (1942) was the 20th film serial (of 57) released by Columbia Pictures. Directed by Spencer Gordon Bennet, it stars Bill Elliott, Slim Summerville, and Carmen Morales.
Plot.
In this serial, Wild Bill Tolliver and Missouri Benson are a pair of adventurers who ride into the vast New Mexico Territory in search of Bill's father, Henry Tolliver, who mysteriously disappeared while prospecting for gold. They soon discover that a ruthless outlaw leader, Jonathan Kincaid, owns an immense mine of gold in which he uses captured Mexican patriots, among others, to work as slaves in the mine. They also learn that Kincaid has joined forces with Colonel Carl Engler, a renegade eastern European soldier, to carry out his cruel intentions. Then Bill and Missouri meet with Consuelo Ramírez, a diligent Mexican agent, who informs them that Bill's father is among the prisoners in the mine. After that, the heroes find themselves in a conflict with the outlaws in the middle of incessant fights, chases and action.
Production.
Writing about the film's atmosphere, Cline says that this serial was a "grim tale...[with a] mood of ominous dread." Missouri was added to the cast because a normal comedy relief character would have not have worked.
Chapter titles.
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