9. Party In Avengers Tower
After a scene showing Ultron assembling himself thanks to some sort of mistake made by Iron Man, cue the title card and a shift into the party scene where each of the heroes attempt to lift Thor's hammer. There could be cuts here back and fore to Stark's lab, but it definitely appears to be a very light and very Joss Whedon scene with lots of humour. It's then of course that Ultron arrives, uses Iron Man's Iron Legion to take the team down and make his escape. The devastation here could be huge, with Ultron either taking over Avengers Tower or compromising it in a way which leads to the heroes being forced to flee. Tony will also probably admit to creating Ultron here, leading to Thor choking him.