Peter O'Toole, whose nuanced performance as "Lawrence of Arabia" managed to make the epic biopic filmed under the dazzling Arabian sun a dark study of disillusionment and shattered dreams, has died. He was 81.

O'Toole's agent Steve Kenis said the actor died Saturday at a hospital following a long illness.

"Lawrence of Arabia" made O'Toole, who had already made his mark on the British stage, an instant movie star and earned him the first of eight best actor Academy Award nominations, even though he never won. He received an honorary Oscar in 2003.

Im Memoriam: Peter O'Toole Dead at 81

His performance in "Arabia," a box office and critical success, would have seemed to set him up for major stardom, but he was never inclined to play it safe, either in his choice of roles or how he played them.

In a 1981 interview, he told ABC News' Bill Diehl he enjoyed taking risks in his film roles.

"Must do it … constantly go to the well … constantly try, try, try. Dare. Dare, Dare. Who dares wins," O'Toole said. "Barrymore, John Barrymore said an actor can only be as he dares to be bad. Yes, taking people to the edge."

Peter O'Toole: A Life in Pictures

His greatest roles were those, like Lawrence, walking the edge between sanity and madness. It is notable that his criticism of his performance in "Lord Jim," adapted from Joseph Conrad's novel of a sailor trying to redeem himself after an impulsive and uncharacteristic act of cowardice, was that he did not go far enough.

"It was a mistake and I made the mistake because I was conservative and played safe. And that way lies failure," he said.

Throughout the 1960s and early 1970s, O'Toole made one critically acclaimed film after another, including "Becket," "What's New Pussycat," "The Night of the Generals," "The Lion in Winter," "Goodbye, Mr. Chips," and "Man of La Mancha."

In 1972's "The Ruling Class," he played a young British lord who inherits a fortune - but believes he is Jesus, and is set upon by relatives who want to wrestle the riches away from him. O'Toole's brilliance is that what starts as the character's accepted madness comes to seem like the possible truth.

But O'Toole, a notorious carouser, suffered serious illnesses in the 1970s, partly due to heavy drinking, which threatened to destroy his career.

In the early 1980s made a comeback in films like "The Stunt Man" and "My Favorite Year," in which he could almost have been playing himself - although the part was also modeled on other Hollywood bad boys such as Errol Flynn.

Throughout the 1980s and 1990s he balanced his career with weighty roles in films like Bernardo Bertolucci's "The Last Emperor" and in light comedies like "Club Paradise" and "King Ralph."

O'Toole continued to work right up until his death. His most recent best actor nomination was for "Venus" in 2006, in which he plays an aging nearly forgotten actor who finds rejuvenation in his friendship with a young woman.

(Credit: Silver Screen Collection/Getty Images)