From highly acclaimed author Alice Henderson comes the eagerly anticipated and electrifying fourth book in the Alex Carter series, in which the wildlife biologist encounters anti-immigrant vigilantes, rugged terrain, and threatening intruders in search of a sleek, powerful, and furtive animal—the jaguar.

When wildlife biologist Alex Carter is tasked with locating jaguars on a vast desert preserve in New Mexico, she is ecstatic. While jaguars once roamed throughout the Southwest, they are now endangered, with only a handful remaining, and Alex hopes some of the sleek and elusive creatures have found their way to the protected sanctuary.

Meanwhile, an archaeological team is excavating the gravesite of a sixteenth-century Spanish conquistador on a neighboring piece of land. Curious about the dig, Alex meets the team and, while learning about their discoveries, she encounters a dangerous group of anti-immigrant vigilantes roaming the area, threatening the archaeology team, demanding they leave. And when the militants learn of Alex's mission, they become bent on stopping her. Because jaguars are federally endangered, the vigilantes worry that if Alex finds them, concessions will be made so that wildlife can cross the border wall. And they want no one crossing it...

And then there are the strange holes that keep appearing on the preserve—Who is digging them, and what are they looking for?

As tensions mount, Alex soon finds herself in a fight for her life against those who would prevent her from restoring jaguars to their historical habitat.