At the Hollywood premiere of Iron Man 3, Whedon said that he had completed a draft of the script, started the storyboard process, and met with actors.Whedon also mentioned that he wrote with Downey in mind and included a "brother/sister act" from the comic books, Whedon explained his rationale for including the characters in the film saying, "their powers are very visually interesting.Stark and Banner discover an artificial intelligence within the scepter's gem, and secretly decide to use it to complete Stark's "Ultron" global defense program. Rogers, Romanoff, and Barton find Ultron and retrieve the synthetic body, but Ultron captures Romanoff. This "Vision" and the Maximoffs accompany the Avengers to Sokovia, where Ultron has used the remaining vibranium to build a machine to lift a large part of the capital city skyward, intending to crash it into the ground to cause global extinction. Later, with the Avengers having established a new base run by Fury, Hill, Cho, and Selvig, Thor returns to Asgard to learn more about the forces he suspects have manipulated recent events.
The Avengers are like a world power, and not everybody's on board with the Avengers coming in and starting fights, even in the name of justice.
So you need that dissenting voice, and you need to understand it and sympathize with it." Because Marvel Studios shares the film rights to Quicksilver and Scarlet Witch with 20th Century Fox and had to avoid conflict with Fox's X-Men films, Whedon introduced two important characters into the Marvel Cinematic Universe completely on his terms for the first time, which allowed him to connect their origin stories to the universe that they created and avoid the concept of mutants.
Second unit filming began in February 2014 in South Africa with principal photography taking place between March and August 2014.
The film was primarily shot at Shepperton Studios in Surrey, England, with additional footage filmed in Italy, South Korea, Bangladesh, New York City, and various locations around England.
For a long time I thought, 'Well, it's just not going to happen.' Then when I actually started to consider it, it became so clear that I desperately wanted to say more about these characters, it would've been an easy no and it was a spectacularly easy yes.
There was no wrestling." Feige revealed that Captain Marvel, who is scheduled to appear in her own MCU film in 2019, appeared in an early draft of the screenplay, but was removed since the character had not yet been cast, saying, "It didn't feel like the time.One of the problems I had on the first one was everybody basically had punchy powers … [Scarlet Witch] can weave spells and a little telekinesis, get inside your head.There's good stuff that they can do that will help sort of keep it fresh," Whedon stated that the twins allowed him to add more conflict: "They don't like America, and they don't like the Avengers…Whedon, the director of the first film, was brought back on board in August and a release date was set.By April 2013, Whedon had completed a draft of the script, and casting began in June with the re-signing of Downey.While in post production, the film was converted to 3D and over 3,000 visual effects shots were added. Escaping with the scepter, Ultron uses the resources in Strucker's Sokovia base to upgrade his rudimentary body and build an army of robot drones.