Brodie, a metalhead teenager, moves in with his strict Christian relatives after his mother's mental breakdown. Struggling to fit in, he befriends Zakk, a fellow outcast who shares his passion for heavy metal music. Together, they form a band and stumble upon some ancient sheet music that they decide to play for fun. Little do they know, the music has supernatural powers and inadvertently summons an ancient demon. As their small town starts descending into chaos with people turning into demonic entities, Brodie and Zakk realize they must find a way to reverse the curse they unintentionally set upon the community.

As the terrors escalate, Brodie seeks help from his crush, Medina, and other friends to fight the growing demonic presence. They arm themselves with makeshift weapons and a heavy metal attitude to face the possessed townspeople and dark forces. A mix of blood-splattering horror and humor follows as the group attempts to navigate the chaos they've unleashed while trying to survive and save the town from total destruction. The journey is filled with adrenaline, camaraderie, and a race against time to find a solution before all hope is lost.