Joss Whedon, the visionary behind Marvel's "Agents of S.H.I.E.L.D." and creator of cult horror comedy TV series "Buffy The Vampire Slayer," has been boning up points with fans to bring the best work he can to the much-anticipated sequel of the third highest grossing film of all time, "Avengers: Age of Ultron."

In an interview with Empire Magazine via /Film, Whedon was probed on whether he will return to the franchise in the near future, especially with Marvel Studios and Disney Entertainment confirming the "Avengers: Age of Ultron's" successors, "Avengers: Infinity War Part 1" and "Avengers: Infinity War Part 2."

"I couldn't imagine doing this again," Whedon said. "It's enormously hard, and it [will] be, by [the time I would make 'Avengers 3 & 4'], a good five years since I created anything that was completely my own. So it's very doubtful that I would take on the two-part Infinity War movie that would eat up the next four years of my life. I obviously still want to be a part of the Marvel Universe -- I love these guys -- but it ain't easy. This year has been more like running three shows than any year of my life. It is bonkers."

In "Avengers: Age of Ultron," Tony Stark tries to jumpstart a dormant peacekeeping program, but things go awry. Earth's Mightiest Heroes, including Iron Man, Captain America, Thor, The Incredible Hulk, Black Widow and Hawkeye, are put to the ultimate test as the villainous Ultron emerges. It is up to the Avengers to stop him from enacting his terrible plans, and soon uneasy alliances and unexpected action pave the way for an epic and unique global adventure.

Marvel's "Avengers: Age of Ultron" stars Robert Downey Jr., who returns as Iron Man, along with Chris Evans as Captain America, Chris Hemsworth as Thor, and Mark Ruffalo as The Hulk. With Scarlett Johansson as Black Widow and Jeremy Renner as Hawkeye, and Samuel L. Jackson as Nick Fury and Cobie Smulders as Agent Maria Hill, the team must reassemble to defeat James Spader as Ultron, a terrifying technological villain hell-bent on human extinction. Along the way, they confront two mysterious and powerful newcomers:Wanda Maximoff, played by Elizabeth Olsen, and Pietro Maximoff, played by Aaron Taylor-Johnson. They also meet an old friend in a new form when Paul Bettany becomes Vision.

Written and directed by Whedon and produced by Kevin Feige, Marvel's "Avengers: Age of Ultron" is based on the ever-popular Marvel comic book series "The Avengers," first published in 1963.

The Avengers return in Marvel's "Avengers: Age of Ultron" on May 1, 2015.

Check out the Comicbook.com gallery to see images from the upcoming blockbuster.