In latest 'Avengers: Age of Ultron' movie news, new details regarding the upcoming film were revealed after the synopsis leaked online.

"Marvel Studios presents Avengers: Age of Ultron, the epic follow-up to the biggest Super Hero movie of all time. When Tony Stark tries to jumpstart a dormant peacekeeping program, things go awry and 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 fate of the planet hangs in the balance," reads the official outline released by Disney.

"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," it went on to say.

The origin of future Avengers members Vision, Scarlett Witch and her brother Quick Silver were also revealed in the aforementioned outline.

"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, and meet an old friend in a new form when Paul Bettany becomes Vision," according to the released outline.

Earlier this year, the movie's director talked about his feelings regarding the film's newest villain, Ultron.

"I'm having a blast with Ultron," said Whedon to Empire Magazine in April, "He's not a creature of logic - he's a robot who's genuinely disturbed. We're finding out what makes him menacing and at the same time endearing and funny and strange and unexpected, and everything a robot never is."

Robert Downey Jr. will return to the blockbuster movie series as Iron Man in order to lead the all-star cast of superheroes against Ultron.

Samuel L. Jackson (Nick Fury), Chris Evans (Captain America), and Scarlett Johansson (Black Widow) are among the numerous actors set to reprise their roles when the smash hit returns to the big screen on May 1, 2015.