The trail crew meet up with a troop of buffalo soldiers - usually freed slaves recruited post Civil War for the US cavalry out west. A rebellious, former sergeant (played by Woody Strode), repeatedly busted down to private for various infractions, is befriended by Rowdy Yates (Clint Eastwood). Killing a fellow soldier in self-defense, the distrusting rebel runs, taking Rowdy's horse. Rowdy is forced to pursue him, hoping he will give himself up.
—deforest