Chris Hemsworth and Scarlett Johansson lead the star power on the red carpet of the Avengers: Age of Ultron premiere. 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.
