Dungeon Games (Masters and Mercenaries #6.5)

Obsessed:

Derek Brighton has become one of Dallas’s finest detectives through a combination of discipline and obsession. Once he has a target in his sights, nothing can stop him. When he isn’t solving homicides, he applies the same intensity to his playtime at Sanctum, a secretive BDSM club. Unfortunately, no amount of beautiful submissives can fill the hole that one woman left in his heart.

Unhinged:

Karina Mills has a reputation for being reckless, and her clients appreciate her results. As a private investigator, she pursues her cases with nothing holding her back. In her personal life, Karina yearns for something different. Playing at Sanctum has been a safe way to find peace, but the one Dom who could truly master her heart is out of reach.

Enflamed:

On the hunt for a killer, Derek enters a shadowy underworld only to find the woman he aches for is working the same case. Karina is searching for a missing girl and won’t stop until she finds her. To get close to their prime suspect, they need to pose as a couple. But as their operation goes under the covers, unlikely partners become passionate lovers while the killer prepares to strike.