It's 1942 in the Appalachians, and Sage's best friend Del has lied about his age and gone off to war because it pays better than working in the coal mine.

The mine took his Daddy's life, and Sage's Daddy's too.

And now, on Christmas Eve, a cave-in threatens more lives - including Sage's Papaw.

Sage knows there are haunts - ghosts - around the town, men who have died in the mine. She's seen one for the last few months on Wren Mountain.

And when she sees that haunt flee into the mine, she knows she has to follow.

Even if it puts her own life in terrible danger...