Alan Silvestri had already scored Romancing the Stone for Robert Zemeckis when the director brought him onto Back to the Future (1985), made by Steven Spielberg's Amblin Entertainment for Universal. The brief was short: the music had to be big. Silvestri took that literally, writing for a 98-piece ensemble credited as the Outatime Orchestra, then the largest assembled for a Universal score. The scale is a deliberate contrast with the small-town setting, lending Marty McFly's predicament the weight of a matinee adventure. At its centre sits a heroic brass fanfare designed to register within a few notes. Spielberg reportedly doubted the composer until he heard the orchestra rehearsing that theme.
The Score in the Film
Silvestri rations the theme, letting suspense cues and lighter material carry long stretches so that full statements land with force. The payoff is the clock tower climax, as Doc scrambles to reconnect a loose cable and Marty drives the DeLorean towards the lightning strike that will supply 1.21 gigawatts. Here the music accelerates with the cutting rather than merely decorating it. When the car hits 88 miles per hour and vanishes, the fanfare finally breaks loose. Elsewhere the orchestration can feel heavier than quieter scenes need, and the Huey Lewis and the News songs do more to define the film's picture of 1985.
Legacy
The score earned Silvestri two Grammy nominations, yet for years listeners could hear only a fraction of it: the 1985 MCA album held just two orchestral tracks. Intrada's limited two-disc set in 2009 presented the complete score at last, plus darker alternate versions. Silvestri returned for both sequels and later co-wrote the music for the stage musical with Glen Ballard, which premiered in Manchester in 2020. That the theme survives its own ubiquity says a great deal about how tightly it was written.