Dive into the world of Maddie Castle, a retired K9 handler turned private investigator, in this heart-pounding collection of the first three novels in the bestselling series. From gripping mysteries to life-threatening pursuits, Maddie and her canine partners battle danger, corruption, and their own pasts to bring justice to those who need it most.

When autistic dog rehabilitator Maddie "Mad Girl" Whitney discovers a corpse on her neighbor's ranch, she impulsively tries to drum up business by claiming that psychic abilities led her to the victim . . . with devastating consequences. Maddie's forced to start a K-9 Search and Rescue team with her ex-girlfriend's twin, a hostile sheriff, or risk losing her beloved former military dog. She reluctantly begins reaching out to others . . . and finds friendship and kindness in the unlikeliest of places.

Caitlyn Reed and her dog, Renegade, are thrown into the midst of murder and intrigue when they discover a dead body while on a trail ride in the black hills of Wyoming. The local sheriff is hell-bent on a conviction, and Caitlyn’s brother, Dylan, is in his crosshairs. Desperate to prove his innocence, Caitlyn turns to Deputy Colt Branson for help, but she must grapple with their rocky romantic past to gain his aid. As Caitlyn and Renegade pursue the killer, the investigation catapults their lives in a dangerous new direction.

After a betrayal that almost took his life, Detective Joel Standage is deskbound. A new assignment is his chance to find out if he still has what it takes to be a cop. His mission? Get close to Mollie Crane, a woman who’s as guarded—and wounded—as he is. Her service dog, Magnus, trusts Joel before she does. When it becomes clear that his interest in her crime boss ex-husband is putting her in danger, what started as a case becomes personal, and Joel will do whatever it takes to protect her…

Drones were supposed to make life easier for Jessie and her search and rescue dogs. Instead, they've made everything a lot more complicated. Her equipment confiscated, her very freedom threatened, Jessica Anderson finds herself in the crosshairs of both law enforcement and a vicious killer when her drones discover a body on the slopes of Long Peak.

K-9 officer Jared Miles stumbles upon a crime scene on his day off and believes Kassie Ashbaugh is the victim of a random attack. However, as threats on her life continue, he realizes that Kassie is in grave danger. Her father's abandoned boat suggests foul play, and Jared suspects someone is after Kassie for something her missing father is hiding. Can Jared unravel the mystery before unknown enemies catch her?

When a young girl is found dead in the mountains outside Timber Creek, lifelong resident Officer Mattie Cobb and her partner, K-9 police dog Robo, are assigned to the case that has rocked the small Colorado town. With the help of Cole Walker, a local veterinarian and single father, Mattie and Robo must track down the truth before it claims another victim. But the more Mattie investigates, the more she realizes how many secrets her town holds. And the key may be Cole's daughter, who knows more than she's saying.

It’s tough working nights with the NYPD. The crime rate is high, the hours are terrible, and forget about a personal life. So, when Officer O’Reilly and her K-9 Rolf switch over to the day shift, things look up. She’s even able to find time for a new boyfriend. But when the theft of a priceless painting from the Queens Museum leaves a fellow police officer dead, Erin and her four-legged partner find themselves dealing with dangerous criminals, sleazy art dealers, and obstructive detectives in a race to capture the killers...and just maybe bring closure to a 75-year-old crime.

Meg and Hawk are part of the FBI's elite K-9 unit. Hawk can sniff out bodies anywhere - living or dead - whether it's tracking a criminal or finding a missing person. When a bomb rips apart a government building on the National Mall in Washington, D.C., it takes all of the team's extensive search-and-rescue training to locate and save the workers and visitors buried beneath the rubble.

After their last deployment, when she got shot, her fiancé, Martinez, got killed, and his bomb-sniffing dog, Elvis, got depressed, soldier Mercy Carr and Elvis were both sent home, her late lover’s last words ringing in her ears: “Take care of my partner.” On the Fourth of July weekend, when all of Northshire celebrates with fun and frolic and fireworks, the dog alerts to explosives and they find a squalling baby abandoned near a shallow grave filled with what appear to be human bones.

Alone in the wilds of mountainous Asia, Jett undertakes an undercover military operation. With threats all around her, alone is the last thing she should be. So, when help arrives, she's ready to get off the cliff's edge and back to civilization. But when her teammates K9 partner shows up carrying a plea for help, nothing will stop Jett from racing to the rescue. Not even a sexy Delta Force operator on a mission.

A head injury as a child gave Haley an extraordinary sense of smell. Her gift allows Haley and her German shepherd, Jax, to be one of the most successful search and rescue teams in the Midwest. When girls begin disappearing with tragic results in her hometown, Haley teams with the county’s new sheriff, Dane Campbell, to find the killer. Haley is drawn to the outgoing sheriff, whose daughter is emotionally damaged. As the murders test Haley’s gift and skills, she learns that sometimes a search and rescue can be about the heart, and the heart can lead the way home.

While hiking in the foothills of the Rocky Mountains, FBI Special Agent Kendra Dean and her K9 partner, Baxter, stumble upon a dead body stashed in the woods. The discovery changes both of their lives forever. Special Agent Rick Sanchez hunts a serial murderer who is targeting women on a multi-state killing spree. Kendra Dean, an agent Rick met on a joint mission six months ago, has found the most recent victim. Rick and Kendra once shared a tempting chemistry but time and miles made their spark a distant memory.

Wilderness expert and dog trainer Raine Stockton agrees to help lead a survival skills training camp for her fiancés executive team. She is unaware that she and her tracking dog, Cisco, are walking into a hotbed of corporate intrigue involving espionage and stolen technology. Everyone at the retreat is a suspect, and no one can be trusted. And none of them is aware that, while their small drama plays out, a much bigger threat is stalking them.

Mason "Mace" Reid lives on the outskirts of Chicago and specializes in human-remains detection. He trains dogs to hunt for the dead. Reid’s coming off a taxing year - mourning the death of a beloved springer spaniel as well as the dissolution of his marriage. He adopts a rescue dog with a mysterious past - a golden retriever named Vira. And when Reid begins training Vira as a cadaver dog, he comes to realize just how special the newest addition to his family truly is....