Wolf Kill

by Cary J. Griffith

Published 29 July 2021

In this outdoors thriller, the investigation of a bizarre wolf attack leads to evidence of murder, conspiracy, and shocking family secrets.

A decades-old promise haunts Sam Rivers, but the wildlife biologist refuses to return home—not with his abusive and estranged father still there. Rivers left the family farm some 20 years ago. He found solace in nature and built a respected career as a special agent for the U.S. Fish & Wildlife Service. His experiences have given him a penchant for understanding predators—a skill he’ll need, now, more than ever.

After his father’s mysterious death, Rivers is lured back to his hometown of Defiance, in northern Minnesota, to fulfill his mother’s dying wish. But all is not as it seems. Rivers breaks into his childhood home during a howling winter storm and discovers something sinister. His suspicions are heightened after a bizarre wolf attack on local livestock. The events lead the special agent to a series of clues that could change everything he knows—or thinks he knows—about the town, his family, and himself.

With the help of alluring reporter Diane Talbott, Rivers must unravel the wolf kill and learn what really happened to his father—a man Rivers has hated for most of his life. It is a case unlike any he’s worked before. His knowledge of frigid winters, wolves, and wilderness will be put to the test, as he tries to solve the case—and stay alive.

In Wolf Kill, natural history writer Cary J. Griffith introduces readers to Sam Rivers, the predator’s predator, and weaves a masterful tale of danger and suspense in the far north.


Cougar Claw

by Cary J. Griffith

Published 21 July 2022

In this outdoors mystery, special agent Sam Rivers investigates the unexplained—and very unlikely—cougar attack that killed a wealthy business owner.

The sighting of a cougar in the Minnesota River Valley, outside the Twin Cities, is incredibly rare. A deadly cougar attack on a human in this area is about as likely as getting struck by lightning—twice. Yet when wealthy business owner Jack McGregor is found dead, the physical evidence seems incontrovertible.

Sheriff Rusty Benson brings in Sam Rivers, a US Fish & Wildlife (USFW) special agent and a wildlife biologist, to examine the scene and sign off on his conclusions. But Sam’s experiences have given him a penchant for understanding predators, and he has more questions than answers.

Details begin to surface that challenge law enforcement’s open-and-shut case. To find justice, Sam must take matters into his own hands. He enlists the help of reporter Diane Talbott and his wolf-dog, Gray, who’s in training to become a working dog for the USFW. Gray’s nose leads the investigation in unexpected directions. The more rocks Sam turns over, the more motives for murdering McGregor seem to slither out.

With no help or support from local law enforcement, Sam and his team are all that stand between justice and those who might otherwise get away with murder. Sam’s knowledge of backcountry, cougars, and the criminal mind will be put to the test, as he tries to solve the case—and stay alive.

In Cougar Claw, natural history writer Cary J. Griffith brings back Sam Rivers, the predator’s predator, and pens a puzzling mystery filled with suspense and intrigue.


Killing Monarchs

by Cary J. Griffith

Published 27 July 2023

Two dead bodies and too many coincidences to ignore—in this outdoors mystery, special agent Sam Rivers must stop a murderous conspiracy.

As a special agent for the US Fish & Wildlife Service, Sam Rivers has researched and studied a variety of animals. He’s visiting sixth graders at Hopkins Elementary to share photographs of the Monarch butterfly—and he’s brought along his drug-sniffing wolfdog, Gray, to give students a demonstration of his partner’s remarkable skills.

Gray finds a sample drug packet, hidden by Sam, but that’s not all. The wolfdog keeps following his nose, leading Sam to a utility room where they discover the school’s janitor, dead. Local police write it off as a drug overdose, but Sam is no stranger to crime scenes. He suspects foul play.

When Sam and Gray come upon a second victim, the coincidences are too great to ignore. Sam starts turning over rocks—and what slithers out is more insidious than anyone could have foretold. Sam’s instincts tell him there’ll be more deaths, but those instincts put him at odds with conventional law enforcement. Armed with his knowledge of the natural world and his wolfdog companion, Sam must uncover answers to questions that few others believe exist.

The Denver Post calls Sam Rivers the “predator’s predator.” In Killing Monarchs, natural history writer Cary J. Griffith brings back Sam for his third mystery—a thrilling novel filled with action and suspense.


Rattlesnake Bluff

by Cary J. Griffith

Published 24 July 2025

When the mysterious appearance of an endangered snake leads to murder, special agent Sam Rivers must solve the case before those responsible can slither away.

The appearance of a rattlesnake wouldn’t normally be enough to halt construction on Alta Vista, an upscale housing development in Southeast Minnesota’s bluff country. But this is no ordinary reptile; it’s a rare eastern massasauga rattlesnake (EMR). The endangered snake has not been seen in the region for more than two decades, so Sam Rivers is called in. As a special agent of the US Fish and Wildlife Service, Sam takes his responsibilities seriously—especially when it comes to protecting endangered species and their habitats. If he finds EMR dens on the construction site, he’ll close it permanently.

While the developers protest in outrage, Sam enlists the help of herpetologist Gina Larkspur from the Department of Natural Resources. Together, they begin to find anomalies that call the entire situation into question. When Sam’s wolfdog, Gray, tries to sniff out the EMR dens, it isn’t rattlesnakes he finds. Instead, Gray discovers the remnants of a terrible, 25-year-old crime. Were the endangered species merely pawns in a diabolical coverup? As Sam searches for the truth, bodies begin to pile up. He and his team must race to find answers before more innocents die.

Natural history writer Cary J. Griffith brings back Sam Rivers for his fifth outdoors-themed mystery—a suspenseful novel filled with fast-paced action.