The two or three top-billed actors in a movie will usually be announced prior to the title of the movie; this is referred to as "above-title billing". For an actor to receive it, he/she will generally have to be well-established, with box-office drawing power. Those introduced afterward are generally considered to be the supporting cast. Well-known actors may be given top billing for publicity or contractual purposes if juvenile, lesser-known, or first-time performers appear in a larger role: e.g., Marlon Brando and Gene Hackman were both credited before the title in "Superman" (1978), while Christopher Reeve, the then-unknown actor who played the titular character and protagonist, was not, even though Brando only appears in the introduction while Hackman was the main antagonist. Similarly in "Apocalypse Now", Brando was billed first though he only appears at the end as the film's chief antagonist, while Robert Duvall was billed second despite a brief supporting role that earned him an Oscar nod for Best Supporting Actor, and Martin Sheen who portrayed the main character was billed third.