Avengers: Age Of Ultron Spoilers - 16 Things We Know Will Happen

16. Tony Tries To "Cure" The Hulk

It was established pretty early in the first Avengers film that Tony Stark was almost perversely intrigued by Bruce Banner's ability to transform into Hulk and it would seem that the second film sees the pair teaming up to work on working out how to control his "powers" a little better, or to cure him entirely. Mark Ruffalo has talked up the fact that the film will look into Banner's internal battle for supremacy and the fact that Hulk doesn't like being a cameo, and that would appear to be a big part of the film's events:

"His ability to handle the Hulk really gets thrown into question in this film. The hard part is coming back. Hulk doesn't want to cede his place. It's much harder to come back from being Hulk than it is to get into him."

And thanks to the officially released image inside Stark's lab above, it looks like Stark and Banner do create something that looks suspiciously like a Hulk serum, designed, no doubt to help Banner reclaim control when he Hulks up. How that research, and Banner's own work in gamma radiation leads to the creation of Ultron remains to be seen, but it looks like the most likely cause.