An advocate for endangered species,  Kelsi Gorman travels to the Brazilian Amazon to investigate rumors of a mysterious black jaguar the size of a saber-toothed tiger. Instead, the enormous cat finds her knee-deep in mud, blood, and smugglers.

Jaime Salazar, one of a few surviving all-male jaguar shifters, encounters a scent he'd never thought to find –female jag shifter. Jag queens exist only in the elders' stories, but someone's staked out a she-cat like poacher bait.

In a fit of primal instinct, Jaime marks Kelsi as his mate. Now, no other female will arouse him. To avoid a long celibate life, he is forced to woo his reluctant mate to be. But first, he must keep her alive.