Cuno Massey may be a federal fugitive, but he's Deputy U.S. Marshal Spurr Morgan's best chance to run down a gang of gunrunners. A wagon train of rifles, ammunition, Gatling guns, and dynamite was stolen by U.S. cavalry deserters who intend to sell the weapons to a Mexican general waging war against Yaqui Indians. To even the odds against them, Cuno and Spurr form an alliance with Ojos de Fuega—“Fire Eyes”—a Yaqui queen as savage as she is beautiful, and her band of renegades. With so much firepower and so many deadly players on the warpath, Cuno and Spurr know that they're sitting atop a powder keg with a sizzling fuse…