Amy Larson & Hunter Forrest FBI

You can cut off the head of the snake, but another will emerge. When two hikers go missing within a series of daunting caves outside of Denver, Colorado, FDLE special agent Amy Larson and her partner, FBI special agent Hunter Forrest, have good reason to suspect foul play. The pair of hikers are only the latest to vanish after a rash of disappearances that's left local law enforcement stumped. But in searching the dank caverns near the Arkansas River, the agents aren't prepared for the horror they uncover: a muddy pit littered with corpses. Covered in bite marks. Made by human teeth. When a tiny toy horse is found on the scene, Amy and Hunter recognize the calling card. They'll have to move quickly before the already sizable body count grows. Their investigation soon draws them down the rabbit hole of a dangerous cult with a sinister mandate, one that involves human sacrifices. Anything to further their twisted cause. But when more people go missing, it becomes clear the cult's reach extends beyond state lines, leading Amy and Hunter deep into the Florida Everglades to set a perilous trap, one that stands to risk everything they hold dear, including their lives.

Death comes for everyone. Deep in the Florida Everglades, the body of a woman is discovered in pieces, presumably ravaged by an alligator. Upon closer inspection, it’s determined no animal could make such perfectly precise cuts. Only a blade could do that. Wielded by a human. Soon, dozens of oil drums emerge amid the river of grass. Each one packed to the brim with body parts. FDLE special agent Amy Larson and her partner, FBI special agent Hunter Forrest, share a bad feeling that extends beyond the horrifying nature of the grim discovery. They’ve seen this kind of sadistic killing before, and when a small beige horse is discovered at the bottom of one of the barrels, they know exactly what it means. The fourth horseman of the apocalypse rides a pale horse—and his name is Death. With so many bodies to identify, connecting one victim to the next is easier said than done. But finding a pattern in the chaos might be the only way Amy and Hunter can zero in on the killer, testing their skills as agents—and their relationship—like never before. And when the disturbing trail of clues signals these slayings are only the beginning, the agents will have to return to where it all started, before it’s too late. The apocalypse is coming, and Hunter and Amy only have one chance to stop it, even if it means sacrificing each other.