Victor Spinetti, who was an established British film star in 1963 when he agreed to make a movie with a pop group called the Beatles and who became famous ever after as the only person besides the four Beatles to appear in “A Hard Day’s Night,” “Help!” and “Magical Mystery Tour,” died on Tuesday in London. He was 82.

The cause was cancer, said a spokesman for his longtime theatrical agent, Barry Burnett.

Mr. Spinetti appeared in scores of plays and about 30 other movies, acting alongside stars like Laurence Olivier, Elizabeth Taylor, Richard Burton and Peter Sellers. He won a Tony Award in 1965. But in the record of 20th-century stage and film history, his modest place in the Beatles’ movie canon pretty much defined him.

The good-natured Mr. Spinetti embraced his role as an eyewitness to Beatles history, appearing at fan conventions around the world in later years to tell stories about making the films and about his friendship with John Lennon.

His most often-told tale was about how the Beatles had drafted him for their first film project. They were popular in Britain but still months away from their first trip to the United States and their debut on “The Ed Sullivan Show.” Mr. Spinetti, a British television veteran by then and fresh from a starring role in a hit British movie, “The Wild Affair,” was appearing in the London musical satire “Oh What a Lovely War” when Mr. Lennon and George Harrison visited him one night backstage.