Dead Mountain

The novel opens on Halloween night in the Manzano Mountains of central New Mexico. Two drunk fraternity brothers from South Valley Tech, Brandon Purdue and Mike Kottke, crash their Jeep on a closed Forest Service road and shelter in a cave. They light a fire and throw rocks at prehistoric petroglyphs (rock carvings), triggering a small cave-in. When Purdue tries to sleep, he uncovers a human skull with braided hair and desiccated flesh.

FBI Special Agent Corrie Swanson, still processing the death of her previous mentor, Agent Hale Morwood, is assigned a new mentor: Supervisory Special Agent Clay Sharp. Special Agent in Charge Julio Garcia gives them the cave case. At the site, Corrie asserts authority over Sheriff Hawley of Torrance County and determines the remains are Ancestral Pueblo burials protected by NAGPRA (the Native American Graves Protection and Repatriation Act). She enlists archaeologist Dr. Nora Kelly of the Santa Fe Archaeological Institute to document the site.

Over coffee, Sharp tells Corrie about an unsolved tragedy called Dead Mountain. In 2008, nine graduate students from the New Mexico Institute of Technology vanished during a Halloween backpacking trip through the Manzanos. Their tent was found with the front door unzipped but a side wall slashed open from inside. Footprints showed hikers fleeing barefoot into a blizzard at 10 below zero. Three bodies were found frozen around a campfire a mile away in their underwear, with severe burns. Two more, discovered months later in a ravine, had been crushed so violently that bone fragments pierced their organs, yet their skin was unbroken. Clothing tested positive for plutonium, uranium, and tritium: radioisotopes that can only originate from a man-made source such as a nuclear weapon or reactor. The results were classified. Three bodies and the expedition's camera and journal were never recovered.

When Nora surveys the cave, Corrie uncovers a foot wearing a modern hiking boot on one side and a felt bootie called a valenki on the other. Sharp identifies the remains as almost certainly Paul Tolland, one of the three hikers whose bodies were never recovered, matching original footprint evidence. Nora and her assistant, Stan Morrison, excavate two bodies: Tolland clutching a knife buried in his own chest, and Gordon Wright, another of the missing hikers, curled deeper in the cave. Garcia assigns Sharp as lead on the revived case and makes Corrie his junior partner.

Autopsies reveal Tolland killed Wright in a frenzy of over 70 stab wounds, then died by suicide, driving the knife into his own heart. Nora suggests extreme hypothermia could explain the violence, since severe cold can produce hallucinations and aggression. The Manzano Families Memorial Association reconvenes under the forceful leadership of Melody Ann O'Connell, stepmother of missing victim Rodney O'Connell, who accuses the FBI of a cover-up and promotes a conspiracy theory about a secret government program called the Boston Project.

The Isleta Pueblo Tribal Council asks Nora to repatriate the prehistoric remains. When Sheriff Hawley blocks the operation, Nora's brother, Skip Kelly, a collections manager at the Institute, films the confrontation. Hawley knocks Nora down while grabbing for the phone; Skip pushes the sheriff in her defense. Hawley arrests Skip on felony charges and confiscates the phone. The video is later erased.

The investigation advances on several fronts. At the campfire site, Nora discovers a penknife engraved "MHT," which Corrie traces to a former student whose roommate was Alex DeGregorio, a wealthy pharmaceutical entrepreneur in Indonesia. DeGregorio tells Corrie he knew the victims but was not on the expedition. Corrie and Sharp interview retired FBI agent Robertson Gold, who confirms the radiation results were classified and admits gaps in his original investigation. Corrie proposes that the hikers unknowingly burned frostbitten extremities against the campfire, and hires an avalanche expert who explains the crushed bodies resulted from a collapsed snow cave.

During a tour of Kirtland Air Force Base, Corrie learns about a 1953 presidential bunker built inside the mountains. Sheriff Homer Watts of neighboring Socorro County, a lawman Corrie has worked with before, investigates the murder of former Kirtland employee Benjamin Cheape. Watts discovers a commendation in Cheape's file dated the day after the Dead Mountain incident, and that Rodney O'Connell's father was a retired Kirtland lieutenant colonel. Corrie and Watts interview O'Connell's former girlfriend, Winifred "Helen" Luckie, who reveals Rodney knew about a secret escape tunnel from the bunker, secured by a code based on his birthday.

Master Sergeant Ramsay Brickell, a Kirtland veteran, secretly tells Corrie about what he calls the Hallowe'en Incident. On October 31, 2008, a B-52 jettisoned a decommissioned 10-megaton thermonuclear warhead into the mountains less than a mile from the hikers' camp. The conventional explosives detonated without triggering the nuclear core, sending radioactive smoke into the storm. Kirtland recovered the debris and classified everything. When Sharp and Corrie present this to the base commander, the FBI Director orders them to cease all investigation of Kirtland's connection to the case. Sharp tells Corrie the order itself confirms the bomb drop happened.

Corrie realizes the bomb alone does not explain why hikers slashed out the side of a tent whose door was open, or why Tolland murdered Wright. She believes O'Connell likely reached the bunker with the camera and journal. Against Sharp's orders, she enlists Nora, who uses lidar (laser-based terrain mapping) and satellite imagery to locate a promising site on Escarabajo Peak. They snowmobile from Rancho Bonito, a nearby dude ranch, into rugged backcountry and find a camouflaged steel door. Corrie enters O'Connell's birthdate on the keypad.

A concrete tunnel opens into a marble hallway with chandeliers and gilded mirrors: a miniature White House. In the bedroom, O'Connell lies mummified on the bed, the journal and camera beside him. The journal lists 10 expedition members, not 9; the first name is Alex DeGregorio. O'Connell's entries reveal that DeGregorio insisted the group drink hot chocolate he had prepared, and within half an hour everyone except DeGregorio experienced terrifying hallucinations. The bomb explosion intensified their drugged panic. When a figure in a hazmat radiation suit (one of the searchers) appeared in the tent doorway, the hikers slashed their way out in blind terror. Tolland, experiencing drug-induced psychosis, murdered Wright. O'Connell, fully dressed because he had been cooking, fled with the journal and camera, reaching the bunker with his father's code but finding no food, water, or way out.

Before they can escape, DeGregorio arrives with mercenaries seeking the camera, which contains photographic proof of his presence on the expedition. Nora hides the camera inside a grand piano during their flight through the bunker, but Corrie is knocked unconscious. They awaken tied to chairs at the ranch lodge, where the caretaker and his wife have been killed. DeGregorio confesses: He synthesized a psychoactive compound from desert toad venom and tested it on the hikers without their knowledge. The drug later became Impremazol, a blockbuster antidepressant. Sharp, unable to reach Corrie, deduces her location and arrives with Watts. They burst in as DeGregorio presses a gun to Corrie's head. Watts's shot deflects the bullet so it only grazes Corrie's temple. The mercenaries are killed; DeGregorio survives, gravely wounded.

In Skip's trial, Deputy Baca, a Torrance County sheriff's deputy who was present when Hawley arrested Skip and the prosecution's key witness, breaks under cross-examination and admits he lied. Baca recounts the truth: Hawley knocked Nora down, Skip defended her, and the sheriff erased the video. The jury returns a verdict of not guilty.

Corrie wakes during a vacation with Watts to find a newspaper headline revealing the bomb drop, DeGregorio's arrest, and the full solution to Dead Mountain. She and Watts deduce that Sharp leaked the story. The 15-year-old mystery is finally solved.