For his role as the dedicated revolutionary leader Pasha Antipov in Doctor Zhivago (1965), he was nominated for an Academy Award for Best Supporting Actor, but was bested by Martin Balsam. Among his other well-known films is King & Country, directed by Joseph Losey, where he played opposite Dirk Bogarde; the all-star war film, Operation Crossbow, directed by Michael Anderson (starring George Peppard and Sophia Loren); King Rat, directed by Bryan Forbes and costarring James Fox and George Segal; and The Night of the Generals, directed by Anatole Litvak with Peter O'Toole and Omar Sharif. He provided physical slapstick comedy in the ultimately chilling anti-nuke black comedy "The Day The Fish Came Out" in 1967. In 1969 and 1971, he was in two spy-comedies, Otley (in the title role) along with "Catch Me A Spy" (1970) starring Kirk Douglas and previously, in 1968, he co-starred in a serious film of that genre, A Dandy in Aspic (1968) opposite Laurence Harvey.