If you've ever wanted to see Weezer frontman Rivers Cuomo's eyes light up with the kind of pure, unadulterated joy that can only come from pillaging your own beloved alt-rock hit for a tuneful ragtime send-up, today is your day.

He did just that when Weezer joined Jimmy Fallon on The Tonight Show to turn the band's 1994 bundle of joy "Buddy Holly" into a full-on barbershop-style chorale, reimagining the ditty with Fallon's comical "Ragtime Gals."

Decked out in some supremely colorful suits, Cuomo and Fallon sang the retooled tune alongside Weezer drummer Pat Wilson, bassist Scott Shriner and guitarist Brian Bell, flanked by comedians Tom Shillue and Chris Tartaro.

Back in the day, the original "Buddy Holly" music video took viewers to another time period entirely. Weezer invaded the idyllic '60s scenes of sitcom Happy Days in the breakout jam that saw the Los Angeles rockers' star skyrocket.

Longtime Weezer heads know well the group's fondness for barbershop-style songs. In the mid-'90s, a harmonious run-through of "My Evaline" was included as a b-side to the band's "Undone — The Sweater Song" single.

Weezer recently hooked up metal fans with a cover of Black Sabbath's "Paranoid," sung by Bell, included on their recently released Teal Album. (Cuomo's known to be a longtime shredder.) The band's Black Album hits March 1.

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