Accomplished British actor Michael Sheen was born in Wales and studied at the Royal Academy of Dramatic Art. As a performer at the Royal National Theatre as well as on Broadway, some of his theatrical credits include Jimmy Porter in Look Back in Anger, Henry V in Henry V, and Wolfgang Amadeus Mozart in Amadeus. In 1993 he made his television debut as a mentally challenged abandoned kid in the BBC miniseries Gallowglass. His made his feature-film debut two years later as Loco Oliver Parker's Othello, followed by a small part in Stephen Frears' Mary Reilly. Perhaps his best-known role to U.S. audiences was his portrayal of Robbie Ross, the close personal friend of literary icon Oscar Wilde (played by Stephen Fry) in Wilde (1997). As a voice actor, Sheen has read several of Wilde's works and other works of classic literature for Naxos Audio Books. He's also contributed to many programs for BBC Radio 4 and World Service. After he and actress Kate Beckinsale had their first child, he starred in the independent drama Heartlands and made a small appearance in the Victorian-era adventure The Four Feathers. In 2003 he was cast as werewolf leader Lucien in Len Wiseman's action fantasy Underworld, with Beckinsale starring as the vampire warrior on the opposing side of an immortal battle. The same year he completed work on sci-fi adventure Timeline, the stylish period film Bright Young Things, and the romantic comedy Laws of Attraction.
He continued to work steadily, but enjoyed his biggest breakthrough returning to the role of Tony Blair for director Stephen Frears when he played opposite Helen Mirren in The Queen. Two years later he would play David Frost to Frank Langella's Richard Nixon in Frost/Nixon, a part he played on stage as well. He had a memorable turn as football manager Brian Clough in the sports drama The Damned United, and played Tony Blair again in the made for cable The Special Relationship. He became part of the Twilight series, taking the part of Aro in New Moon, and sticking with the franchise all the way through to the conclusion.
In 2011 he played a pontificating intellectual in Woody Allen's Oscar-winning Midnight in Paris, and two years later he appeared opposite Tina Fey and Paul Rudd in the comedy Admission. In 2013, he began a starring role in Showtime's Masters of Sex, playing human sexuality researcher William Masters.