In 1967, Scorsese made his first feature-length film, the black and white I Call First, which was later retitled Who's That Knocking at My Door, with fledgling actor Harvey Keitel.
De Niro had known De Palma for several years previously, and his first film role in collaboration with De Palma materialized in 1963 at the age of 20, when he appeared in The Wedding Party.