A stagecoach arrives in Dodge City with an injured driver, a dead passenger, and an empty case that held $5,000 gold from the Denver Mint. The driver, Billy Hanley, claims that he recognized one of the masked robbers by his voice. Wyatt figures that Billy's story doesn't add up when he confirms that the accused man has an alibi. Then Billy turns up dead, leaving a grief-stricken girlfriend, schoolteacher Miss Nancy, to mourn his death (thetvdb.com)