Torn between her duties to the FBI and her need to keep her loved ones safe, former black-ops army sniper Mercy Gunderson must unleash the cold, dark, merciless killer inside her and become the predator… rather than the prey.

When tragedy strikes again, Mercy is ready to throw all her energy into her own investigation, and she’s out for revenge. As she digs up the truth behind the shocking crimes, Mercy uncovers dark and dangerous secrets and must race to stop a killer before everything she’s fought for is destroyed forever.

Newly minted agent Mercy Gunderson is back and ready for action- unfortunately, she’s stuck doing paperwork in an overheated government office building. But she gets more than she bargained for when she’s thrown into her first FBI murder case, working with the tribal police on the Eagle River Reservation, where the victim is the teenage niece of the recently elected tribal president. When another gruesome killing occurs during the early stages of the investigation, Mercy and fellow FBI agent Shay Turnbull are at odds about whether the crimes are connected.

Due to job confidentiality, Mercy can’t discuss her misgivings about the baffling cases with her boyfriend, Eagle River County sheriff Mason Dawson, and the couple’s home on the ranch descends into chaos when Dawson’s eleven-year-old son Lex is sent to live with them. While Mercy struggles to find a balance, hidden political agendas and old family vendettas turn ugly, masking motives and causing a rift among the tribal police, the tribal council, and the FBI. Soon, however, Mercy realizes that the deranged killer is still at large—and is playing a dangerous game with his sights set on Mercy as his next victim.

Buy Now From


“Lori Armstrong’s writing is as smart, sexy, and ruthless as her characters. MERCILESS is her best novel yet.”
Alison Leotta, author of DISCRETION and LAW OF ATTRACTION

“Armstrong’s heroine blows away the stereotypes. Suspense lovers who haven’t met Mercy Gunderson are missing out. MERCILESS has it all–a chilling mystery, smart dialogue, and memorable characters. Another riveting addition to the Mercy Gunderson series.”
Laura Griffin, bestselling author of TWISTED

“Driven, damaged and dangerous, FBI agent Mercy Gunderson is one of the best female leads to come down the pike since Eve Dallas. Lori Armstrong delivers the goods with MERCILESS.”
Cindy Gerard, bestselling author of THE BODYGUARDS and THE BLACK OPS series

“Mercy is one of the best female characters around, and you can quote me on that.”
Lisa Gardner, bestselling author of LOVE YOU MORE and LIVE TO TELL

“Some may consider her the female answer to the rural/western hardboiled authors who have been putting a new spin on the genre as of late. When you read her, you’ll discover she has her own distinctive voice and proves she can deliver anything as down and dirty and tough as any of the good ol’ boys with a pen.”
Scott Montgomery of MysteryPeople

“This extremely exciting page-turner is a new title in the popular series that surrounds Mercy Gunderson…Readers will love being by Mercy’s side yet again as they witness a dual personality that is highly addictive! This is one character that will not soon disappear (thankfully) from the suspense genre.”
Suspense Magazine

“Armstrong has a knack for presenting a strong sense of place and deftly brings readers onto the reservation to expose them to a culture and way of life that most will find virgin ground. She also has a way with dialogue…Armstrong’s writing is spot on…”
Kirkus Reviews

“This is a hard hitting murder mystery that has a kick-ass female leading the way.”
Night Owl Suspense

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