Scott had originally planned next to adapt a version of Tristan and Iseult, but after seeing Star Wars, he became convinced of the potential of large scale, effects-driven films. He accepted the job of directing Alien, the 1979 horror/science-fiction film that would win him international success. Scott made the decision to switch Ellen Ripley from the standard male action hero to a heroine. Ripley (played by Sigourney Weaver), who appeared in the first four Alien films, would become a cinematic icon. The final scene of John Hurt's character has been named by a number of publications as one of the most memorable in cinematic history. Filmed at Shepperton Studios in England, Alien was the sixth highest-grossing film of 1979, earning over $104 million worldwide. Scott was involved in the 2003 restoration and re-release of the original film. In promotional interviews at the time, Scott indicated he had been in discussions to make a fifth film in the Alien franchise. However, in a 2006 interview, Scott remarked that he had been unhappy about Alien: The Director's Cut, feeling that the original was "pretty flawless" and that the additions were merely a marketing tool. Scott later returned to Alien-related projects when he directed Prometheus and Alien: Covenant three decades after the original film's release.
Scott directed Hannibal (2001) starring Anthony Hopkins as Hannibal Lecter. The film was commercially successful despite receiving mixed reviews. Scott's next film, Black Hawk Down (2001), featuring Tom Hardy in his film debut, was based on a group of stranded US soldiers fighting for their lives in Somalia; Scott was nominated for an Oscar for Best Director. In 2003, Scott directed a smaller scale project, Matchstick Men, adapted from the novel by Eric Garcia and starring Nicolas Cage, Sam Rockwell and Alison Lohman. It received mostly positive reviews, but performed moderately at the box office.
Scott was appointed Knight Bachelor in the 2003 New Year Honours for services to the British film industry. He received his accolade from Queen Elizabeth II at an investiture ceremony at Buckingham Palace on 8 July 2003. Scott admitted feeling "stunned and truly humbled" after the ceremony, saying, "As a boy growing up in South Shields, I could never have imagined that I would receive such a special recognition. I am truly humbled to receive this treasured award and believe it also further recognises the excellence of the British film industry."