It’s hard to imagine “The Godfather” without Al Pacino. His understated performance as Michael Corleone, who became a respectable war hero despite his corrupt family, goes almost unnoticed for the first hour of the film — until at last he asserts himself, gradually taking control of the Corleone criminal operation and the film along with it.

But there would be no Al Pacino without “The Godfather,” either. The actor was a rising star of New York theater with just one movie role, in the 1971 drug drama “The Panic in Needle Park,” when Francis Ford Coppola fought for him, against the wishes of Paramount Pictures, to play the ruminative prince of his Mafia epic. A half-century’s worth of pivotal cinematic roles followed, including two more turns as Michael Corleone in “The Godfather Part II” and “Part III.”