In Bill & Ted Face the Music, the titular characters' music band Wyld Stallyns play a song called "Face the Music" that is so great it unites humanity and saves all of reality. But during filming, before the song was actually created, the band took the help of a classic Beatles melody to find their world-saving groove.

In an interview with THR, lead actor Alex Winter revealed that director Dean Parisot took the film's music very seriously, and did not want to be put in a position where the song would have to be defined while filming was underway. Instead, Parisot wanted to create the song in post, once he had a better sense of the film's general vibe. Thus, during production, Bill and Ted rocked out at their reality-saving concert to The Beatles.

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"We played to 'Ob-La-Di, Ob-La-Da' by The Beatles," said Winter, "[Dean] knew he wanted that tempo, and so we needed a beats per minute (BPM) that would actually be the beats per minute of the final song. Otherwise, it wouldn't have synced, obviously; it wouldn't have worked." Winter added that Parisot used a fully-cut concert of Bill and Ted playing "Ob-La-Di, Ob-La-Da" that he then used to build the new song from scratch.

While the movie presents "Face the Music" as the greatest song ever written, Winter said he loved that Parisot did not try to make the song too grandiose, but instead focused on finding the comedy in grounded natural moments and make a song that would suit the scene at the concert. "He wanted the emotion and the performance to carry the song," explained Winter, "He didn't want to try to pretend that whatever the notes were were somehow the greatest song of all time. He just wanted something that would support the performance."

Directed by Dean Parisot and written by Chris Matheson and Ed Solomon, Bill & Ted Face the Music stars Keanu Reeves, Alex Winter, Anthony Carrigan, Kid Cudi, Brigette Lundy-Paine and Samara Weaving. The film is now in theaters and on premium video on demand.

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