We take a look at the best dressed Hollywood stars to hit the red carpet for the premiere of Avengers: Age of Ultron. In the film Iron Man (Robert Downey Jr), Captain America (Chris Evans), Thor (Chris Hemsworth), The Incredible Hulk (Mark Ruffalo), Black Widow (Scarlett Johansson) and Hawkeye (Jeremy Renner) face a malevolent artificial intelligence.
