The film “Back to the Future” (one of the greatest movies of all time) is about a 17 year old boy named Marty McFly who travels back in time to the year 1955 through his friend Doc’s invention. Once he arrives, he soon accidentally runs into his parents and changes certain events. He has now altered history to a point where he will never be born. His objective is to get his parents to fall in love while a younger version of his friend Doc fixes the time machine. In the “Gigawatts” scene, Marty is showing young Doc how the time machine works through a recording he did of old Doc. Here young Doc discovers the machine requires 1.21 gigawatts to function, which immediately shocks him.

Later on in the scene, Marty and Doc come up with the idea to use a bolt of lightning as the energy source. Before they come up with this idea, the scene only contains diegetic sound. There have been no instruments played so far and everything we hear the characters can hear as well. Music is introduced into the scene once this idea is thought of. This is when the scene begins to develop nondiegetic sound, only we can hear the instruments. The music starts off with a slow tempo, giving the idea something containing hope is about to occur. It then picks up the pace to a fast exciting tempo once the idea is introduced. The audience is now on the edge of their seats excited with anticipation. The audience knows their plan is going to be a success.