Goliath, Thor, Wasp, Yellowjacket and a SHIELD team are closing in on Ultron-6 as he pulls the switch to blow up New York with a nuclear explosion. But the explosion doesn't happen, and Ultron beats a strategic retreat.
Vision appears, and explains that, even though weakened by blasts from Ultron and SHIELD last issue, he had become intangible and infiltrated Ultron's machinery. There he had materialised and wrecked it. He hopes this makes up somewhat for the fact that he had rebuilt Ultron in #66 out of indestructible adamantium, under his preprogrammed commands.
The android collapses and the Avengers take him back to the mansion, and feed him energy through the jewel in his forhead. Vision still doesn't revive, but Yellowjacket uses a mind-probe to extract an image from his brain, the image of the molecular rearranger. In #66 we learnt that this is the only thing that can affect adamantium.
The Avengers contact the inventor of adamantium Dr MacLain on the SHIELD helicarrier. But he tells them that the molecular arranger is gone, and they guess that Ultron has it within his body.
Yellowjacket contacts Black Panther, whose men are fighting off invaders in Wakanda, and asks for some vibranium.
The Avengers lay a trap for Ultron by sending MacLain to the UN. Ultron senses it is a trap, but still wants MacLain who is the only one who can make more adamantium so Ultron can have an army of indestructible robots.
Ultron attacks as Ultimate Ultron. Ultron-6 was embedded in a flying platform. This version walks. Goliath, Thor and Wasp defend MacLain, but Ultron captures him and tries to extract the secret of adamantium from his mind.
Something disrupts Ultron and seems to be destroying him. He swears to take New York with him, and prepares to turn himself into a nuclear explosion. But Thor covers him with a vibranium dome, which contains the blast.
Dr Maclain turns out to be Hank Pym in disguise, and he had infected Ultron's brain with the thought 'Thou shalt not kill'.