Invited to a wedding at the Great Refuge of the Inhumans, the Avengers find themselves, the Fantastic Four, and the Inhumans fighting both mind-control and insurgency.
The Avengers receive a personal invitation from Gorgon and Lockjaw to attend the wedding of Quicksilver and the Inhuman, Crystal. The wedding is news to Quicksilver's sister, the Scarlet Witch, because her brother refuses to talk to her as long as she is romantically involved with the android, Vision.
When the Avengers arrive at the Great Refuge, the hidden lunar home of the Inhumans, they are greeted by the other Inhumans and the Fantastic Four. Amidst the celebrations leading up to the wedding, some of our heroes start acting strange - insulting and attacking the Alpha Primitives, and then falling unconscious. RN-62 of the Alpha Primitives makes use of these attacks to foment rebellion against the ruling Inhumans.
Out of the blue the bride is grabbed by the giant Omega, a creation of the evil genius, Maximus. He originally was created to start an insurgency by the Alpha Primitieves against the ruling Inhumans. His strength was derived from the 'secret guilt' that the Inhumans had for enslaving the Alpha Primitives. Originally Omega had been defeated when the Inhumans recognized and dealt with their prejudice. Since that time they had implemented laws that declared all Inhumans as equals.
Assuming that Maximus was behind the reappearance of Omega, Black Bolt went to check on him, only to find the villain unconscious. Then the Alphas began to attack, led by the instigator, RN-62. The heroes were fending them off, until one by one they started to lose consciousness.
When Omega appears, it just gets worse when our heroes become paralyzed. Vision recognizes this kind of attack, and is proven right, when Omega rips off his face to reveal a giant... ULTRON-7!