Aliens from the planet Zeta Reticuli invade Earth after the American Air Force shoot down one of their ships in the Nevada desert. Seeking to negotiate the retrieval of their comrades, the Aliens instead encounter an aggressive American administration who will stop at nothing to obliterate the intergalactic threat.

As the world searches for a cure to a disastrous virus, a scientist and park scout venture deep in the forest for a routine equipment run.

Pinhead is stuck in a block after the Big Confrontation in "Hellbound," The block containing Pinhead and the puzzle cube is bought by a young playboy as sculpture. Pinhead busies himself escaping by getting the playboy to lure victims to his presence so he can use their blood. Once free, he seeks to destroy the puzzle cube so he need never return to Hell, but a female reporter is investigating the grisly murders and stands in his way.