Ben Kingsley is to appear in Iron Man 3. The Hugo actor is in final negotiations to star in the forthcoming Marvel blockbuster as an enemy of Tony Stark/Iron Man - played by Robert Downey Jr. - though the exact details of the character are being kept under wraps.

Variety, however, reports the villain is expected involved in the spread of a virus through nanobots because the film is believed to be loosely based on the 2005 Extremis comicbook series. News of the story arc may disappoint some fans as it had previously been speculated the next movie in the series would see the titular character take on his original archenemy the Mandarin, a wealthy Chinese scientist and martial arts exert who backed the warlord who imprisoned Stark.

Jon Favreau - who directed the first two films in the franchise - had previously expressed an interest in exploring the character, but he has moved on from the series, with Shane Black at the helm of Iron Man 3. Shane is also co-writing the script with Drew Pearce.

Joining Ben and Robert in the movie will be returning stars Gwyneth Paltrow, Scarlett Johansson and Don Cheadle. Production is set to begin in May, and the film has a scheduled release date of May 3, 2013.