Two brothers, reunited for their father's funeral, stumble upon the entrance to a nearby cave, where they are slowly forced to confront the true, nightmarish cause of their father's death. Inside the hidden cavern, the brothers discover a fist-sized hole leading to an unexplored virgin passage. Ted and Brade descend into obsession, returning day after day in a relentless effort to widen the opening and gain access to the terrifying unknown passage beyond.