Well, it is called "The Avengers."

"They're angry and they want vengeance," said Aaron Taylor-Johnson of he and co-star Elizabeth Olsen's "Age of Ultron" characters (brother-sister duo Quicksilver and the Scarlet Witch) while stopping to chat with us at San Diego Comic-Con. So how did the characters arrive at a place of such rage? Fans of the comic books more or less know the backstory, and - in its broad strokes at least - their bio doesn't appear to have been dramatically altered in the journey from page to screen.

"They're from Eastern Europe, and they've lost their parents from an early age, and they have each other, that's it," said Johnson of the characters' tortured background. "They look out for one another...my guy in a very kind of protective physical way, and Scarlet Witch in a very sort of grounded, psychological, sort of mothering, nurturing kind of way."

To hear more from the stars, including what it was like developing the characters alongside writer-director Joss Whedon, click on the video above for the full interview.

"Avengers: Age of Ultron" hits theaters on May 1, 2015.