'Parks and Rec' Stars Bid Farewell with 'Bye, Bye Li'l Sebastian' Singalong

Leslie Knope and the gang hit up 'Late Night' to celebrate the show's series finale.

Leslie Knope and the gang showed up on Late Night with Seth Meyers on Thursday to celebrate the bittersweet Parks and Recreation series finale.

Led by Mouse Rat frontman Chris Pratt, Amy Poehler, Aziz Ansari, Nick Offerman, Aubrey Plaza, Adam Scott, Retta, Jim O'Heir, Mike Schur and Jon Glaser ended the evening by singing a beloved Pawnee tune, "Bye, Bye Li'l Sebastian."

Holding up lighters during the singalong, Aubrey and Jim, a.k.a. April Ludgate and Jerry Gergich, started to simulate making out to the surprise of their co-stars.

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The Parks and Rec cast also sat down with Seth to chat about how they thought the series should have ended. "I pitched that I would have sex with Joe Manganiello," Retta, who plays Donna Meagle on the NBC sitcom, joked (sorta).

Pratt, who portrays the lovable Andy Dwyer, apparently thought the audience should see how everyone died "like the Six Feet Under finale."

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"When you saw April, it would be she died of a broken heart," Pratt futher explained. "And then you would see that Andy died because he was left in a hot car with the windows rolled up."

What did you think of the Parks and Rec series finale? Share your thoughts in the comments and tweet #ETnow.