It would have been just another performance of the new Fall Out Boy single last night on the 'Conan' show, but for a few Spinal Tap-inspired moments.

First, as in the 1984 film, bassist Pete Wentz got stuck in an on-stage cocoon. Then -- turn it up to 11! -- Derek Smalls (actually actor Harry Shearer, of course) took over on bass. That funny reference to "Rock and Roll Creation" from Rob Reiner's mock rockumentary wasn't the only tip of the hat to Spinal Tap. As Fall Out Boy continued performing 'My Songs Know What You Did in the Dark,' a miniature Stonehenge figurine could be seen on stage, and they were soon joined a series of dancing druid-like creatures.

In a backstage interview frontman Patrick Stump said the film still resonates with Fall Out Boy not just because it's funny, but because so much of the humor hits so close to home for working bands like themselves.

"I won't lie -- my parents would watch 'Spinal Tap,' and I didn't know it was a joke," Stump said. "I was like, 'This is awesome.' That's part of what is so lasting about it, is that it's so real. So many bands have said that to us: 'I can't even laugh at Spinal Tap; it's too real.'"

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