Yuma Prison is a fetid hellhole filled with the dregs of humanity - killers, thieves and backstabbers who'd kill over a scrap of meat. Now it's home to Frank Morgan, who's posing as an inmate. A ruthless outlaw named Cicero McCoy has buried a fortune in stolen bank money in a harsh, desolate little piece of hell known as Ambush Valley. To get Cicero to lead him to the loot, Frank has become Cicero's new best friend behind bars - and co-plotter of a daring breakout. Soon, the last gunfighter and a stone-cold killer are blazing away at enemies on both sides of the law. Until the time comes for Frank Morgan to make a fatal choice - and for one of them to die...