A woman off the grid.

Darby Graham thinks she's on a much-needed vacation in remote Idaho to relax. But before she even arrives at the ranch, an earthquake strikes—her first clue that something is amiss. Then when a cabin on the edge of town is engulfed in flames and problems at the ranch escalate, Darby finds herself immersed in a chilling mystery.

A town on fire.

A serial arsonist sends taunting letters to the press after each fire. As a forensic linguist, this is Darby’s area of expertise . . . but the scars it’s caused her also the reason she’s trying to escape from her life.

A growing darkness.

As the shadows continue to move in, the pieces of the town around her come into sharper focus. Can she trust the one man who sees her clearly?