If you've never seen the movie 'This Is Spinal Tap,' then Fall Out Boy's performance of 'My Songs Know What You Did on 'Conan' last night probably made little-to-no-sense to you. The Chicago band recreated a scene from the 1984 mockumentary when the Spinal Tap bassist, played by Harry Shearer, got trapped in a theatrical pod that the band was using on stage.

Unlike the movie however, Pete Wentz found a replacement in none other than Harry Shearer himself! The man was just waiting for his redemption! When Wentz was finally released, he gave Shearer a fist bump and took over his part on the high-energy rendition of the band's single from their latest album. It seems as though Fall Out Boy may have actually saved rock and roll last night!

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