In the ruins of Caswell, Maine, Carter Bennett learns the truth of what had been right in front of him the entire time. Desperate for answers, he takes to the road, leaving family and the safety of his pack behind, all in the name of a man he only knows as a feral wolf. Wolves are pack animals, and the longer Carter is on his own, the more his mind slips toward the endless void of Omega insanity.
Carter pushes on, following the trail left by Gavin, the son of Robert Livingstone and half-brother of Gordo Livingstone. Gavin's history with the Bennett pack goes back further than anyone knows, a secret kept hidden by Carter's father, Thomas Bennett. The violent battle that follows threatens the entire pack, and the humans of Green Creek, as what Carter finds changes the course of the wolves forever.
Brothersong is the fourth and final novel in TJ Klune's Green Creek series.