When Dylan Russell unintentionally kills his ex-lover, Tommy, he knows he's in trouble. Then he meets a man named Mars Marsden who offers him a solution—join the covert organization C21. An outfit made up of good men and women who ended up on the wrong side of the law, C21 now gives these people a chance to track and punish those criminals to whom the law doesn't seem to apply. Dylan should fit right in. After meeting Mars' handler, Dylan learns Tommy was an arms trafficker. Somewhat reluctantly, he agrees to go undercover to help bring down the rest of Tommy's gang. After this dangerous induction into his new life, Dylan is sent for training. But Dylan is a marked man. Not only are the police looking for him, but when one of Tommy's old colleagues discovers where Dylan is being trained, things get interesting. Can he and Mars survive the jobs they're sent on? And, more importantly, can their purely sexual relationship deepen into something more before the work they do tears them apart?

A C21 Story Sean Miller is a professional thief. When he breaks into the home of C21 handler Jonah and is discovered, Jonah makes him an offer he can't resist—join the covert organization and put his talents to a more legitimate use. C21 skirts the edges of the law, bringing criminals to justice that the police can’t seem to catch, and they could use someone with Sean’s talents. For his first job, Sean is teamed with Ken Ward, one of Jonah's men, to bring down a phony adoption racket. In the process, Sean fights his growing interest in Ken, certain it won't be reciprocated. Is he right? Or will the two men become more than just partners when they are teamed up again to stop a gang of jewel thieves?

A C21 Story What's a C21 operative to do when his partner is kidnapped by Barone, the man who runs a prostitution ring Tate and Gwen are trying to shut down? In Tate Butler's case, he unwillingly hooks up with Van Layton, an FBI agent and his ex-lover, to find Gwen, the daughter of Tate's handler. First, they need to locate where Barone has her hidden. Barone is also, according to Van, a drug dealer Van plans on putting out of business. Can Tate and Van put aside their splintered past to find Gwen and stop Barone? Or will working together only destroy the last vestiges of what they once felt for each other?