Covert operative Tom Keen joins forces with Susan "Scottie" Hargrave, the brilliant and cunning chief of a covert mercenary organization that solves problems that are too dangerous for the government.

The Yellowjackets barely made it through summer in the woods, but now as winter begins to bite, hunger and desperation threatens to turn into full-on psychosis. Meanwhile, twenty-five years later, each survivor must ask themselves—is the darkness coming for them, or is it coming from them?