Back to the Future him to 2015 to resolve a problem with their future children. The trio board the DeLorean, which has been upgraded with hover technology, and warp to the future. Writer and producer Bob Gale conceived "Back to the Future" after he visited his parents in St. Louis, Missouri after the release of "Used Cars". Searching their basement, Gale found his father's high school yearbook and discovered he was president of his graduating class. Gale had not known the president of his own graduating class, and wondered whether he would have been friends with his father if they went to high school
Back to the Future shots, which did not satisfy Zemeckis and Gale until a week before the film's completion date. The compositing involved for the film's time travel sequences, as well as for the lightning effects in the climactic clock tower scene, was handled by animation supervisor Wes Takahashi, who would also work on the subsequent two "Back to the Future" films with the rest of the ILM crew. Alan Silvestri collaborated with Zemeckis on "Romancing the Stone", but Spielberg disliked that film's score. Zemeckis advised Silvestri to make his compositions grand and epic, despite the film's small scale, to impress Spielberg. Silvestri began