Every psychopath in the Mulvaney family has a role to play. Archer Mulvaney is the gambler, a drunken reprobate making his living as a high-stakes poker player. Very few people know the real Archer, not even his brothers. But there is one man who knows far too much.

Mackenzie Shepherd spends his days photographing endangered wildlife. He's also the brother of a sociopath and son to the woman who literally wrote the book on raising one. When his mother asks him to head a secret government project, it seems like the perfect excuse to run away from his life.

But running from his past has Mac colliding straight into Archer. And that's a problem. For this project to be successful, Mac and Archer have to agree on every decision, and the two see eye-to-eye on nothing. Except, maybe the sex. The sex is off the charts.

When Mac's old life comes back to haunt him, Archer insists on putting their differences aside to help keep him safe. But Mac, like Archer, is used to solving things on his own. Can they finally stop fighting each other to find the truth, or is their relationship the next thing on the endangered species list?