After weeks of casing a ranch for its prized remuda, a gang of horse thieves pillage everything, leaving the owner's wife dead. Before the distraught man can drown himself in booze, Harry Pendergast of the Denver Detective Agency offers him a chance for vengeance. Because this time, the victim is Brad Storm, aka the Sidewinder. It seems that Brad's ranch isn't the only one that's been brutally hit. There's a huge reward to track down the powerful thieves. But the hunt won't be easy, taking the Sidewinder into dangerous territories and bloody battles. So when a showdown in Wild Horse Valley becomes imminent, Brad hatches a plan, one he hopes will have the villains recoiling in fear before the Sidewinder strikes back.