<P> The sequel was announced in May 2012, after the successful release of 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 . 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 . While in post-production, the film was converted to 3D and over 3,000 visual effects shots were added . With an estimated net production budget of $365 million, it is the second most expensive film ever made . </P> <P> Avengers: Age of Ultron premiered in Los Angeles on April 13, 2015, and was released on May 1, 2015, in the United States, in 3D and IMAX 3D . The film received generally positive reviews from critics and grossed over $1.4 billion worldwide, becoming the fourth - highest - grossing film of 2015 as well as the fifth - highest - grossing film of all time . A sequel, Avengers: Infinity War, was released on April 27, 2018, and another untitled sequel is scheduled for release on May 3, 2019 . </P> <P> In the Eastern European country of Sokovia, the Avengers--Tony Stark, Steve Rogers, Thor, Bruce Banner, Natasha Romanoff, and Clint Barton--raid a Hydra facility commanded by Baron Wolfgang von Strucker, who has been experimenting on humans using the scepter previously wielded by Loki . They encounter two of Strucker's test subjects--twins Pietro Maximoff, who has superhuman speed, and Wanda Maximoff, who has telepathic and telekinetic abilities--and apprehend Strucker, while Stark retrieves Loki's scepter . </P> <P> 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 . The unexpectedly sentient Ultron, believing he must eradicate humanity to save Earth, eliminates Stark's A.I. J.A.R.V.I.S. and attacks the Avengers at their headquarters . 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 . Having killed Strucker, he recruits the Maximoffs, who hold Stark responsible for their parents' deaths by his company's weapons, and goes to the base of arms dealer Ulysses Klaue to obtain Wakandan vibranium . The Avengers attack Ultron and the Maximoffs, but Wanda subdues them with haunting visions, causing the Hulk (Banner) to rampage until Stark stops him with his anti-Hulk armor . </P>

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