Eleven months ago, 911 dispatcher Tessa Quill listened to her sister's final radio transmission before the mountain took her. The official report blamed a tragic winter storm. Tessa blames Rowan Cade.

Rowan was the search-and-rescue captain who refused a direct order to look for her sister. Disgraced, expelled, and living in isolation, he is the last person Tessa wants to see. But when a decommissioned frequency crackles to life with her dead sister's exact final words, Tessa drives into a deadly January blizzard to confront the man who let her die.

Trapped together in a remote mountain cabin by a catastrophic whiteout, Tessa and Rowan are forced into a brutal game of survival. But the sub-zero temperatures aren't the only threat. Rowan has been keeping secrets about what really happened on Garnet Peak, and Tessa's arrival has triggered a deadly countdown. As the temperature drops and the walls close in, the line between enemy and ally shatters. The mountain is hiding a sprawling conspiracy, and the people protecting it are already hunting them.

To survive, Tessa must trust the man she came to destroy. But in the deep snow, every track tells a story, and the truth might be deadlier than the cold.