The Night the Posse Died was the first of four cowboy related novels that Dean would write over the next four years. Each one was released in May of that year. He was tired of the same old "father shot by evil cattle rancher" revenge story or the "innocent guy shoots someone in self defense but is now seen as an outlaw". He wanted to try and push the envelope with the genre.

This story is centered on Cabe McCullan, a professional bounty hunter. McCullan is hired by the state of Montana to track down a wanted outlaw and his gang. He stops in the town of Cross Keys to assemble a posse with the local sheriff. After the posse is assembled they head out to track down the gang of thieves. Someone in the town sold the posse out and had them ambushed. McCullan is the only survivor. He spends the rest of the book tracking down the outlaws while trying to find out who in Cross Keys arranged the ambush.