Though a bit cliché-ridden, Pearse's made-for-TV thriller centers on a group of characters trapped in an isolated sanatorium. The Sanatorium--Le Sommet, now a world-class, five-star Swiss resort--has a dark past. The brainchild of Swiss property developer Lucas Caron, the hotel was once renowned worldwide as a center for treating tuberculosis before the advent of antibiotics forced its diversification. As the novel opens, there are hints that Lucas and his business partner Daniel are struggling. There's talk of bribes and corruption, and Daniel, the principal architect, went missing in the final stages of planning.

Pearse knows from the outset exactly what she wants to accomplish and the kind of crisp yet evocative tone she wants to establish. She introduces us to British law enforcement officer Elin Warner, suffused with anxiety as she arrives at the hotel with her boyfriend, Will. Like everyone else arriving at the hotel on a snowy windswept day, Elin conceals more than her fair share of secrets. A still, silent resignation imbues the entire drama along with a note of regret. Watchful Elin is more layered than first meets the eye, as is the case with the rest of the guests.

Elin is haunted by the loss of her younger brother, Sam, and the role that her other brother, Isaac, may have played in Sam's death. Though she's been prone to the odd panic attack, work has been going well. She has just been promoted to detective sergeant and had landed a big case--until her life contracted, closed down to become something that would have been unrecognizable to her a few years ago. Elin is plagued with a strange and unfamiliar feeling, "something she wasn't even aware that she wanted." Will is openly effusive while Isaac seems preoccupied, though it makes sense that her brother is celebrating his engagement at the hotel. The place, like Isaac, "is all about facades, an attempt to cover up what really lies beneath." Isaac says some pre-engagement family time is in order, though the invite was unexpected. Isaac left for Switzerland over four years ago, and Elin's contact with him has been sporadic at best.

Le Sommet certainly gets inside your head. From the beginning, the building haunts Elin. There's something brutally clinical about the architecture and the institutional air in its stark lines. The glass everywhere is dizzying: "whole walls of it allowing you to see right in." Something is at odds with that clinical feel. Hiding places are everywhere, which isn't helped by the frenetic movement of the snow outside, "sharp white arrows targeting the glass" eclipsed only by murky swirls of fog. Past misdeeds hang over every scene. As lies and rationalizations are exposed, the mask of the "civilized" Le Sommet starts to slip.

Like Agatha Christie, Pearse seems obsessed with intimate relationships and how little it takes to destabilize them. As the ostensibly hospitable weekend devolves into a murderous fever dream, gruesome discoveries that include bodies with fingers amputated, a series of bracelets, and premeditated murders force reluctant Elin to try to figure it all out. She knows that the murders have their roots in something so dark it feels almost tangible. Every element--the impassable avalanche, the gas masks, the glass box, the restrained amputations, the sandbag, the body in the pool--is carefully thought out, perhaps part of a narrative, a story: "an organized crime, an organized killer."

What's happening isn't logical or possible to explain. As the storm rages outside, Elin begins to feel horribly exposed. This was meant to be a break, a chance to relax. Now she is driven to find out what happened to Daniel. Isaac snaps his fingers: "No footprints, no nothing, never found his bag, his phone." There's talk about Daniel's disappearance, his personal and professional relationship with Lucas--gossip, mainly, and accusations of nepotism, rumors that Lucas was about to pull him from the project.

The novel is atmospheric in the swirls of milky, icy frost and the hazy semicircle of the moon, which casts its magnificent soft light across the mountain peaks. The more Erin looks, the more she realizes how sinister the mountains appear, like "raw, jagged spikes." And what secrets does the strange archive hold? They seem to be artifacts stored from when the hotel was a sanatorium with patients. Elin shivers at this "tangible intrusion" of the hotel's past into its present. She's suddenly acutely aware of how little separates her and the guests from what has come before. There's a strange flashing behind Elin's eyes, "not lights but scenes," fragments of moments, melting into one another lucid and bright, a flashback to Isaac's face that day: "something eerily precise, alien."

Classic mysteries often linger in the memory and in popular imagination because they are not just about who did what to whom, but why. Certain characters in The Sanitorium conceal something terrible from the rest of the guests, but they can't hide their worst truths from themselves, and that knowledge slowly sends them close to the edge. Elin stands front and center in the mystery as she descends into the abyss over the biggest secret of all: what originally happened in the sanatorium, this place with its deep, dark riddles.