When they were young, they dreamed of finding the source of their favorite band's inspiration. Now they can only pray it doesn't find them.

In 1973, at the peak of their stratospheric fame, the members of the classic rock band Bad Mother posed for an iconic photo gathered around an old stone well in the woods. That indelible image became the cover of their magnum opus, Wellspring, and the subject of a thousand fan theories concerning what the lead singer found in the well that drove him to new heights of artistic genius and depraved depths of violent madness culminating in the gruesome murder of a fan.

Forty years later, four lifelong friends and former bandmates brought together by their shared love of the classic Bad Mother album are drawn into the dark mystery of its origin when one of them goes missing on an unholy pilgrimage to find the legendary well. For Brian Parker, the prospect of dropping everything to go looking for a friend who never let go of their youthful obsession is an inconvenient obligation but one he can't turn away from after watching Adam's last unsettling video message from the dark forest where the well is rumored to be.

When they arrive at Adam's last known location, Brian and his old bandmates are confronted by secretive and unfriendly locals who declare the forest off limits until the festival of the Hunter's Moon. Defying the taboo and embarking on a treacherous trail, the would-be rescuers soon find themselves wounded, lost, and confronted with all manner of strange occurrences. Adam has left cryptic clues to his whereabouts, but nature itself seems to conspire against them. And while they hunt for their lost friend, Brian can't shake the feeling that something ancient is hunting them.