When Deputy U.S. Marshal Lucas Cain and Deke Pauley forge a partnership on the dusty bounty hunting trail, their camaraderie faces its ultimate test. Struggling to save a ranch owned by a mysterious and affluent woman, fate has a cruel sense of humor when Lucas's trusted companion is mercilessly gunned down by an outlaw, leaving him stranded in the vast wilderness.

Committing to a grueling journey on foot, his path collides with the elegant private rail car of Leah Davencourt. As she becomes the target of a brutal attack, Lucas intervenes and saves her from harm, catapulting him into a world of unexpected opportunities. Grateful for Lucas's bravery, Leah presents him with an offer that could change the course of his destiny-a lucrative bounty for the highly specialized job of locating and safely returning a kidnapped child to his desperate father.

But with the journey far from straightforward and unforeseen challenges rising from a surprising source, Lucas begins to wonder-in the unforgiving business of bounty hunting, is solitude his only reliable ally?