Avengers 2: 21 On-Set Photos You Need To See

Marvel's The Avengers (or Marvel Avengers Assemble as it's clunkily known as in the UK) was a massive box office hit, quickly becoming the third-highest grossing film ever. A sequel was inevitable, and Joss Whedon has returned to helm the much-anticipated Avengers: Age of Ultron, due for release next year. As seems to generally be the case for Marvel superhero films, Age of Ultron is looking to take a much darker direction than the original film. Early posters have shown our band of heroes getting overwhelmed by Ultron's forces, and the "self-absorbed" robot is looking to be the most fearsome foe the Avengers have faced yet. Of course, that's not to say the whole spectacle won't be lightened up by Whedon's snappy writing. We've put together 21 on-set photos from the production of Avengers: Age of Ultron, that show off the cast and crew in action. From explosion-filled battles scenes, to early looks at some of the film's most iconic costumes, each of these will be a treat to any fans of franchise. Please note that there are likely to be spoilers ahead, so read ahead at your peril...

21. Controlled Explosives