The deviant monster GIGANTO bursts up from the underground, putting a quick stop to the Fantastic Four's day off. Now it's up to them to stop the monster from destroying the city, but the FF quickly realize that the giant monster has a specific target… the BAXTER BUILDING! The mystery of the monster's appearance will lead the FF deeper into Subterranea than they've ever gone, and right into a TRAP. The MOLE MAN sent Giganto to attack the FF, but has a grander scheme in the works. Because the only thing better than having Giganto destroy the FF is to control an ARMY of Gigantos.