During the rehearsals the band noticed that the smoke bomb effect was not to their liking so they asked the stage hand to pack a little more of the power into Keith Moon's drum kit to give it a more spectacular effect. However, while the band and the crew went out for lunch, Moon returned and packed even more powder into the drums essentially turning it into a bomb and during the finale of "My Generation" as the band were doing their usual instrument smashing finale, the drums exploded. As a result, Moon suffered cuts on his arm, Pete Townshend's hair caught fire. However, Townshend also suffered permanent damage to a hearing as a result of the prank.