His Christmas Guardian

Trained to be enemies...Do they dare become lovers?

CIA Agent Alex Creed’s mission is to take down a deadly criminal before Christmas…and only Nick Kane stands in his way. The black ops agent claims he's after the same target and that working together is the best plan. Never before has Alex been so attracted to someone he shouldn’t trust. Especially knowing Nick has a bit of a death wish, while Alex envisions a future together... 

From Harlequin Romantic Suspense: Danger. Passion. Drama.

Runaway Ranch series by New York Times bestselling author Cindy Dees:
Book 1: Navy SEAL's Deadly Secret
Book 2: The Cowboy's Deadly Reunion
Book 3: Her SEAL Bodyguard
Book 4: His Christmas Guardian