Warning Signs

In the mountain backcountry, 12-year-old Zach accompanies his father, Bram, on a ski trip to Pantheon Hut, a remote lodge reserved for a weekend investor retreat. The trip takes place one year after Zach's mother, Grace, died under circumstances officially ruled accidental. Much of the story unfolds through Zach's memories of the survival skills Grace taught him, the dynamics of his parents' marriage, and his growing suspicion that his father is far more dangerous than anyone realizes.

The novel opens with a prologue set in 2021, in which Grace teaches Zach and his younger sister, Bonnie, how to assess avalanche danger while skiing to the same hut. Grace guides her children through snow pit tests and explains that the hardest, bravest decision is walking away from something you want in order to stay safe. Her eyes go distant, and Zach senses she is talking about more than snow.

One year later, Zach hikes to the hut with Bram for a trip designed to court investors in Ajax Property Tech, Bram's business. On the trail, Zach discovers a dead elk whose head and neck have been stripped to bloodless bone while the body remains intact. Bram dismisses the sight, seeing the antlers only as something to sell. Through flashbacks, Zach reveals that Bram presents a charming public face but harbors an "Underself," a cold, critical persona that emerges in private.

At the hut, Bram is furious that his assistant, Ginny, has not arrived as promised. While sweeping, Zach pries a diamond earring from between the floorboards, trailing crusted hairs and organic matter, and hides it on a shelf. The guests arrive: Shane Oliver, son of Bram's biggest investor Arlo Oliver; Shane's friend Jon Hensley, a professional skier; Dave Dowling, a wealthy rancher, and his 16-year-old son Russ; Pike Whitlock, a stocky investor; and Steve, a backcountry guide. Shane reveals that Arlo plans to reinvest in Bram's company.

Zach bonds with Russ while building a snow shelter outside, and the two share family secrets. Zach mentions Bram's first wife, Serena, and their son, Abraham Jr., both of whom died in a house fire. Near the shelter, he spots an unidentifiable creature moving through the trees, leaving elongated, clawed tracks. That evening, Dave tells a story about unexplained cattle mutilations on his ranch. During the night, Zach hears something dragging through the snow and an inhuman howl, and watches a dark figure climb the slopes of Mount Mariah before vanishing.

Through an extended flashback, Zach relives his parents' final argument. Grace asked for a separation and revealed she had consulted a lawyer and accountant who believed Bram's business was fraudulent, that the software did not exist, and that investor money had been lost in risky speculation. Bram, after initial fury, grew chillingly precise in extracting what Grace had shown the professionals.

The next morning, the group climbs to the summit of Mariah Bowl. Steve digs an avalanche pit and conducts a compression test that reveals a buried weak layer. He recommends the boys skip the Bowl entirely and urges the group to limit their descent to a less steep route. Jon dismisses Steve's concerns, and Bram pressures the guide into compliance. Zach recognizes the situation mirrors the previous year, when Grace reached a nearly identical conclusion and chose to retreat. He stays silent.

Shane and Jon ski down first, then veer into steeper terrain against the agreed plan. As Russ descends, the snowpack collapses and an avalanche sweeps him away. Zach deploys his airbag pack, survives the slide's edge, then switches his avalanche beacon to search mode and digs Russ out alive. Minutes later, a massive cornice, an overhanging lip of wind-packed snow, breaks from the ridge and releases a second avalanche into the area where Bram, Steve, and Pike have been searching for Shane and Jon.

Zach skis into the debris field alone. He locates and revives Pike, and he and Dave uncover Bram, shaken but intact. They find Shane dead with a broken neck. Continuing the search, Zach's shovel strikes a woman's face. The body belongs to Ginny. Her torso is eviscerated, the damage resembling the elk's mutilation, and one earlobe holds a diamond earring matching the one Zach found in the hut while the other is torn and bloody. After over an hour of searching, the group accepts that Steve and Jon are also dead.

Back at the hut, Zach tells Bram about the earring. Rather than planning to report the murder, Bram sees opportunity. He examines Ginny's phone, finds the text history scrubbed, and constructs a theory that Pike killed Ginny in the hut, impersonated her via text, and dragged her body up the mountain. Bram tells Zach that "people love a dead girl" (225) and plans to use the evidence for blackmail.

That night, Zach borrows Russ's phone, sets it to record, and hides it under a couch. On the recording, Bram reveals he dissolved sleeping pills into the group's drinks to ensure privacy, then confronts Pike with a partly fabricated reconstruction of Ginny's murder. Pike eventually confesses, saying that Ginny's taunt that his father was right to cut him off triggered his rage. Pike is destitute, so Bram pivots, revealing that Grace's life insurance paid a double accidental-death benefit into trusts for Zach and Bonnie, and that Bram receives the funds if something happens to the children. He proposes that Pike kill Zach during the next morning's hike, staging it as an accident. Pike resists but agrees.

Zach listens to the recording before dawn. He hides the earring inside a paper towel roll on the kitchen shelf, wrapped in a note identifying Ginny's killer and Bram's fraud. He flees into the darkness, but his escape downhill is blocked by a steep, avalanche-prone meadow too dangerous to cross, and the phone shows no cell signal. Forced to turn back, he hears Bram and Pike pursuing him and leaps off a ledge to hide. From a distance, he watches Pike attack Bram. The two men fight in the deep snow before Bram beats Pike with a rock, and both tumble off the trail's edge.

Zach retreats to the abandoned miner's cabin he and Grace discovered the year before. He lights a fire and collapses into exhaustion. In the night, an intruder enters, traps Zach inside his sleeping bag, and cinches it shut with a ski strap. The attacker tries to ignite a blanket in the stove, but the damp wool only smolders. Zach realizes the attacker is Bram, who left to retrieve lighter fluid from the hut, planning to burn the cabin down. He escapes through the sleeping bag's second zipper and flees.

In a clearing near a concealed mine shaft, Bram finds Zach and tries to coax him back to the hut. Zach, seeing lighter fluid and dry wood in his father's pack, confronts him, accusing Bram of murdering Grace, Serena, and Abraham Jr. A rescue helicopter sounds in the distance. Bram grows candid, admitting Grace was conscious when he killed her, saying otherwise "she wouldn't have understood what she'd done wrong" (340). He tells Zach the only difference between them is that Zach "failed" (341), and lunges at his son.

A wolverine, the elusive creature that has haunted the mountain throughout the story, emerges from the trees. Bram tries to scare it off, but the animal bares its fangs and advances. As Bram retreats, the snow and earth beneath him collapse into a concealed mine shaft weakened by snowmelt. His scream fades as he falls into the void. The wolverine regards Zach with tentative eyes. Zach speaks calmly: "I am a person. My name is Zach. You don't need to be afraid. He's gone now. It'll all be okay" (346). The wolverine pads into the forest.