All of the movie was filmed to a pre-recorded soundtrack except for the "Pinball Wizard" sequence in which The Who really did play in front of the theatre audience (
Elton John's band, however, is featured on the soundtrack). When the fans rush the stage at the end of the sequence, that wasn't scripted but caused by the excitement The Who's live performance generated, particularly when
Pete Townshend started to smash his guitar.
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