Namor has attacked the surface world in retaliation for years of polluting the oceans, which has resulted in the death of one of his Atlantean subjects. The newly-formed Fantastic Four have been contacted to stop his attack. They hold their own until Namor summons a giant mutated whale named Giganto to regain his advantage.
With the arrival of Giganto, Nick Fury calls up Thor and Captain America to help out. Thing attacks Namor, but is punched through several buildings and lands in the middle of Alicia Masters’ art gallery. Thor manages to stun Namor allowing Cap to step forward to convince his brother-in-arms from World War II to call off his attack. Before a decision is made, Namor suddenly falls ill. He is the victim of the duplicitous Lord Krang who seeks his throne. Richards takes him to a hospital for treatment. He discovers Namor has been injected with a poison made from a sea wasp.
After Thing leaves Masters’ art gallery, he comes upon an idea to stop the giant sea creature. He commandeers one of S.H.I.E.L.D.’s shuttles and flies it directly into Giganto’s mouth with the damaged quantum drive from the prototype shuttle and sets the self-destruct. Thing bails out at the last possible second and is saved by the Human Torch. The quantum drive implodes and disintegrates Giganto.
The revived Namor addresses his army and tells them to lay down their arms; they were all deceived by Krang who was acting in his interests, not those of Atlantis. This victory makes the Fantastic Four the newest media darlings as well as federally sanctioned heroes. They move into the Baxter Building and make it their official headquarters.