Sons of Thunder by William W. Johnstone & J.A. Johnstone

JOHNSTONE COUNTRY. DANGEROUS CURVES AHEAD.
 
Slash and Pecos match wits with the wiliest opponent they’ve ever had—a wickedly smart woman who can’t be caught—in their wildest western adventure yet. . . .
 
It sounds like an easy job: track down the lady friend of notorious outlaw Duke Winter and bring her in for questioning. There’s just one problem: Slash and Pecos have never met a woman like Miss Fannie Diamond, a glamorous showgirl who’s prettier than a French poodle, slicker than a Dodge City gambler, and more slippery than a Mojave rattlesnake. She knows that Slash and Pecos are coming for her and has no intention of being caught—not without one of hell of a fight. . . .
 
By the time the duo arrive at the Rocky Mountain mining camp where Miss Diamond is performing, the devilishly clever gal has already arranged a welcome wagon for them: some hired thugs who knock Slash and Pecos silly. Still, the show must go on—so the pair decide to snatch Miss Diamond off the stage in the middle of a performance. It doesn’t take long for Slash and Pecos to learn that there’s no business like show business—and no showgirl like Miss Fannie Diamond. Sometimes, the female of the species is deadlier than the male. . . .  
Live Free. Read Hard.