Big Calibre

After Bob Neal raises the $60,000 needed to save his father's "Triple N" ranch, an intruder breaks into the ranch house and throws a vial containing lethal gas. Neal's father is killed and the intruder escapes with the money. The next day, Neal discovers that Otto Zenz, the deformed town chemist, is the murderer by matching his footprints with those of the intruder. Realizing he has been discovered, Zenz throws another vial at Neal, who again escapes. Meanwhile, in a neighboring town, Neal's friend, Jim Bowers, prepares to visit the assayer Gadski to pay off his mortgage. Despite his daughter June's pleas that he not go alone, Bowers travels by himself to town, and is shot and robbed on the way. Desperate when her father does not return, June visits Jack Bently, Gadski's partner, who refuses to help unless she accepts his proposal of marriage. After a year of successful uranium prospecting, Neal and Rusty Hicks decide to visit Bowers. On their way, they come across what they believe to be Bowers' remains. Then Neal witnesses an auto stage robbery in which the robber is knocked unconscious. When Neal approaches, he realizes the bandit is June, who is desperate to save her father's ranch. She escapes, leaving Neal to be arrested for the attempted robbery. Rusty then feigns drunkenness in public in order to be arrested and placed in the same cell with Neal. That evening, another vial of poisonous gas is thrown into the cell, corroding the lock so that the two can escape. June hides them in a cave on her property, where Neal realizes that the rich marble deposits in the cave are what Gadski and Bently are after. At a masquerade dance in town, Neal slips a note to Gadski saying that he suspects Gadski in Bower's murder. Gadski and Bently then prepare to escape, and go to the Bowers' ranch so that Bently can kidnap June. Neal arrives and fights with Gadski, knocking off his disguise to reveal that he is actually Zenz. Bowers suddenly appears and explains that after being shot, he was nursed back to health by the Indian Blackhawk. Zenz attempts to escape in an auto stage, which he nearly drives off a cliff. Hanging precariously, Zenz fumbles with a vial of poison and inadvertently kills himself. Neal escapes from the stage before it plummets over the edge, and returns to court June, while her maid Arabella courts Rusty.