Eli Wallach, an early practitioner of method acting who made a lasting impression as the scuzzy bandit Tuco in The Good, the Bad and the Ugly, died on Tuesday at the age of 98, according to the New York Times.
Wallach appeared on the big screen well into his 90s in Roman Polanski's The Ghost Writer and Oliver Stone's Wall Street sequel and other films.
"It's what I wanted to do all my life," Wallach said of his work in an interview in 2010.
Having grown up the son of Polish Jewish immigrants in an Italian-dominated neighborhood in New York, Wallach might have seemed an unlikely cowboy, but some of his best work was in Westerns.
Many critics thought his definitive role was Calvera, the flamboyant, sinister bandit chief in The Magnificent Seven. Others preferred him in The Good, the Bad and the Ugly as Tuco, who was "the ugly", opposite Clint Eastwood in Sergio Leone's classic spaghetti Western.
Years later, Wallach said strangers would recognise him and start whistling the distinctive theme from the film.
Wallach graduated from the University of Texas, where he picked up the horseback-riding skills that would serve him well in later cowboy roles, and studied acting at the Neighborhood Playhouse Actors Studio before World War Two broke out.
"Wallach is the quintessential chameleon, effortlessly inhabiting a wide range of characters, while putting his inimitable stamp on every role," the Academy of Motion Picture Arts and Sciences, which gave him an honorary Oscar in 2010, wrote in a profile on its website.
After serving as an Army hospital administrator during the war, he found work on the New York stage and took classes at the Actor's Studio, which used Method acting in which actors draw on personal memories and emotions to flesh out a role.
He appeared in This Property Is Condemned and ended up marrying the show's leading lady, Anne Jackson - a marriage that also led to several stage and screen collaborations.
Wallach made a name on Broadway with roles in two Tennessee Williams' works, Camino Real and The Rose Tattoo, for which he won a Tony in 1951, as well as a two-year run in Mr. Roberts.
His first movie was another Williams work, Baby Doll in 1956. Other major films included How the West Was Won, Mystic River, The Holiday, Lord Jim and The Misfits - in which he starred with Clark Gable and Marilyn Monroe with John Huston directing an Arthur Miller script - and The Godfather Part 3.
Despite the notable movies, Wallach said it was his portrayal of the villain Mr Freeze on the "Batman" television show of the 1960s that generated the most fan mail.
Wallach titled his autobiography, The Good, the Bad and Me: In My Anecdotage. He and his wife lived in New York and had three children.
The New York Times said his death had been confirmed by his daughter.