Shadow in the Woods

What "Castle Rock" does for Maine, "Monsters in the Green Mountains" does for Vermont.

Six go into the woods. Three come out.
Addie Preston, a new mental health counselor, is flattered when her colleague asks her to co-lead an intensive Ecotherapy weekend for a small group of clients. The band of six head into the remote trails of the Green Mountains.
As a storm engulfs the area, the group takes refuge in a cave off of the trail. No one is prepared for what they will discover.
Or what will discover them.