When Tony Stark and Bruce Banner get all sneaky sneaky and try to jump-start a dormant peacekeeping program called Ultron which, let's be real, just sounds like he's gonna wind up being a bad guy, things go horribly wrong (because conflict and/or fucking duh), and it's up to Earth's mightiest heroes to stop the villainous Ultron from enacting his terrible plan. But first they gotta squabble like a harem of brother-husbands and sister-wives. Civil war...man, you didn't see that coming?