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.

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.

Ryder Creed and his dogs have been making national headlines. They've intercepted several major drug stashes being smuggled through Atlanta's airport. But their newfound celebrity has also garnered some unwanted attention. When Creed and one of his dogs are called in to search a commercial fishing vessel, they discover a secret compartment. But the Colombian cartel's latest shipment isn't drugs. This time, its cargo is human. To make matters worse, Creed helps one of the cartel's drug mules escape.

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.

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.

Rescuing a kidnapped child is part of the job for search-and-rescue K-9 handler Patrick Sanders—but this time it's his son. Now Patrick and his furry partner must work with his high school love, Jennie Wilcox, to shield the little boy he just learned about. In a hurricane's aftermath, Detective Erin Jeffries is stunned when she and her K-9, Alcee, uncover a collapsed building's only survivor—her long-ago ex, Cody Elbourne .When park ranger Autumn Mercer and her K-9 partner, Sherlock, meet a stranger in the mountains whose brother is injured, they drop everything to help.

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.

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…