The Dutch East Indies, at the end of the nineteenth century. An adventurous captain of an American merchant vessel is looking for a sunken Dutch vessel containing 10,000 precious diamonds. Unfortunately, he's not the only one and then there's also that volcano on the nearby island of Krakatau, waiting to explode in its historical, disastrous eruption...

Rancher Clay and his brother, Steve, head out across the Sonora mountain pass, followed by Lednov, an ex-con seeking revenge on Clay for putting him behind bars. Clay and Steve unexpectedly cross paths with a group of dance hall girls -- including Mary, Marcia and Helen -- whose stagecoach has broken down, and help them get to the nearest ranch, where Lednov unfortunately catches up to Clay.

Late in the Civil War, three Confederate soldiers escape from a Union prison camp in Missouri. They soon fall into the hands of pro-Confederate raiders, who force them to act as "outriders" (escorts) for a civilian wagon train that will be secretly transporting Union gold from Santa Fe, New Mexico, to St. Louis, Missouri. The three men are to lead the wagons into a raider trap in Missouri, but one of them starts to have misgivings....

During the Civil War, a Union spy, Andrews, is asked to lead a band of Union soldiers into the South so that they could destroy the railway system. However, things don't go as planned when the conductor of the train that they stole is on to them and is doing everything he can to stop them. Based on a true story.