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.

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…

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.

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.

Eden Mercer, a determined young officer in the fog-shrouded, tight-knit town of Nightfall, Oregon, is haunted by her past in a fundamentalist cult. With her loyal K-9 partner, Shadow, by her side, she’s eager to prove herself in a department dominated by machismo. When a couple stumbles upon a woman’s body in a ritualistic burial deep within the dense, misty forests, Eden is thrust into a chilling mystery. As she delves deeper, disturbing clues and unsettling secrets tied to a local cult emerge.

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.

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.

Former Special Forces operator Sergeant Crew Gatlin takes everything in stride, even the career-ending incident that separated him from the army, half a leg, and his beloved working dog, Havoc K027. Putting his life back together and lying low, he takes a job with A Breed Apart and is unexpectedly reunited with Havoc. It’s too good to be true—and the proof is in their first assignment: to work as a K-9 team for a television drama in Los Angeles.

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?

Loner Boone Hendrix left the military with ghosts that haunt him. He lives with his dog Atlas on a farm in Vermont. Alone. Just the way he likes it. Until he rescues a half-drowned, beautiful brunette from his river. Gemma Newhouse is the daughter of the richest man in America, and from the abrasions on her wrists and her drugged state, she’s on the run from someone dangerous. She’s nothing like Boone expected—sweet, smart, and likes baking—and she ignites a fierce need inside him.

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.

Navy SEAL Jack Daniels (save the jokes, he’s heard them all) and his trusty Belgian Malinois sidekick, Dakota, are back home in Asheville, North Carolina, after a bomb left them scarred. Unable to accept that he’ll never be able to return to his team, Jack is looking for a miracle. What he isn’t looking for is a permanent relationship, though he’s open to a no-strings distraction at the magic hands of gorgeous local potter Nichole Masters.

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.

When her estranged uncle attempts to sabotage her family’s reindeer ranch, K-9 team assistant Katie Kapowski heads home to help save it—and becomes his target. With their rocky past, Alaska State Trooper Brayden Ford and his furry partner are the last team Katie wants assigned to protect her. But with the ranch under siege, they must work together…or risk falling victim to a killer.

Call it a premonition. Call it intuition. Call it anything you like, but Pennsylvania State Trooper Jerry McNeal simply thinks of it as “that feeling.” That feeling may come on without warning, so intense he can’t breathe.

Eden Mercer, a determined young officer in the fog-shrouded, tight-knit town of Nightfall, Oregon, is haunted by her past in a fundamentalist cult. With her loyal K-9 partner, Shadow, by her side, she’s eager to prove herself in a department dominated by machismo. When a couple stumbles upon a woman’s body in a ritualistic burial deep within the dense, misty forests, Eden is thrust into a chilling mystery. As she delves deeper, disturbing clues and unsettling secrets tied to a local cult emerge.

Spencer Quinn’s first original audio short story reveals how everyone’s favorite detective duo - Chet the Dog and P.I. Bernie Little - came to meet before their first big case in Dog On It. As fans know, Chet first met Bernie on that fateful day when he flunked out of K-9 police school. The details of that day, though, have always remained a little vague (like so much in Chet’s doggy brain). All we know is that Chet had been the best leaper in his K-9 class, but for some reason he failed his final leaping test...and that a cat was involved...and that there was some blood. But whose?

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.

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.

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.