Career: Pacino made his film debut in 1969's Me, Natalie, but it was his performance as a junkie in The Panic in Needle Park two years later that prompted director Francis Ford Coppola to cast him as Michael Corleone in The Godfather. The film was a huge hit and earned Pacino his first Oscar nomination. He followed it up with more hits including Serpico (1973), Dog Day Afternoon (1975) and Scarface (1983), but as his movie career appeared to be on the wane during the 1980s, he took a break to return to the theatre. He returned to the screen in 1989 with Sea of Love and, after seven previous nominations, went on to win an Oscar for Scent of a Woman (1992). He continues to combine movies, TV, theatre and directing work - recent projects include Danny Collins (2015) and Misconduct (2016).

Career: De Niro made a handful of films in the 1960s and early 1970s, but it wasn't until 1973's Bang the Drum Slowly and Mean Streets (his first collaboration with Martin Scorsese) that his career took off. He received an Oscar for The Godfather Part II a year later and was nominated Academy Awards for Taxi Driver and The Deer Hunter, and took home his second Oscar for Raging Bull. The King of Comedy, Once Upon A Time in America, Brazil, The Mission, Angel Heart and The Untouchables followed. Over the past few decades, De Niro has made crowd pleasers such as Cape Fear, Casino, Heat, Meet the Parents and Analyze This, as well as directing A Bronx Tale and The Good Shepherd. He gave a fabulous comic performance in the fantasy movie Stardust, before starring alongside fellow big-screen icon Al Pacino in cop thriller Righteous Kill. His more recent films have included Silver Linings Playbook and The Family.

Career: Duvall's first professional work came on stage. His TV debut was in a 1959 episode of Armstrong Circle Theatre, while his first film was 1962's To Kill a Mockingbird. Other early movies were The Chase, Bullitt, True Grit and MASH. In 1972, he received his first Oscar nomination for The Godfather. Nominations since have been for Apocalypse Now, The Great Santini, The Apostle (which he also wrote and directed) and A Civil Action. He won the Best Actor award for Tender Mercies in 1983. Other films include The Godfather: Part II, Sling Blade, Open Range, Secondhand Lions, Thank You for Smoking, Crazy Heart and Get Low.

Career: Keaton made ends meet performing at a nightclub before landing a role on Broadway in Hair, although she refused to take part in the musical's notorious nude scene. The role that changed her career was a part in Woody Allen's stage version of Play It Again, Sam. She went on to star in several of the director's films, including the big-screen adaptation of the play, as well as Sleeper, Love and Death, Manhattan and Annie Hall. She won an Oscar for the latter, and Allen has claimed she was his muse for a period. Keaton has also starred in The Godfather trilogy, Reds, The First Wives Club, Something's Gotta Give and Morning Glory, as well as moving into directing and producing.