Charlize Theron Michael Fassbender London Prometheus Pictures

Fans gathered at London's Leicester Square today to try and get a peek of Charlize Theron, Michael Fassbender, and Guy Pearce at the world premiere of Prometheus. The trio were also joined on the blue carpet by the film's director, Ridley Scott. Charlize, dressed in Christian Dior, is back in the UK following a recent stint there promoting her other major release, tomorrow's Snow White and the Huntsman with costar Kristen Stewart. Michael's in London, his home base, after a weekend of partying at Monaco's Formula One Grand Prix, where he ran into X-Men: First Class costars Jennifer Lawrence and Nicholas Hoult.

This is one of the first major Prometheus event for Charlize, Michael, and Guy. However, the movie's viral video campaign kicked off earlier this Spring. Michael's character, an android named David, gave fans a sneak peek at the alien sci-fi thriller. Next Friday, June 8, Charlize will battle herself at the box office when Prometheus opens against Snow White and the Huntsman. She's also going head-to-head against other A-list celebrities in the PopSugar 100 faceoff — have you voted yet?