Barenaked Ladies sing 'The Big Bang Theory Theme' on Stephen Colbert to mark series finale

As a last hoorah, the cast of The Big Bang Theory assembled on The Late Show‘s Thursday night episode in light of the hourlong series finale that aired on CBS — and they brought the Barenaked Ladies with them.

The music group composed and recorded the original theme song for The Big Bang Theory for when the show first premiered in 2007. On Stephen Colbert’s late-night talk show stage, they came to perform it again — at least one more time — with the actors present.

“I was really honored that they asked me to participate in the finale,” Barenaked Ladies frontman Ed Robertson said in a statement. “It was a really fun and collaborative day in the studio, getting notes back and forth from [executive producer] Chuck [Lorre] while coming up with this new version. It really reminded me of composing and recording the song in the beginning — fun, spontaneous, and with a spirit of playfulness.”

“Our association with the show is something we’re all very proud of, and being involved in so many fun ways as the show draws to a close is really cool,” he continued. “The chance to play the song on The Late Show with the whole cast present is a lovely bookend to an incredible run.”

Jim Parsons, Kaley Cuoco, Johnny Galecki, Mayim Bialik, Kunal Nayyar, Simon Helberg, and Melissa Rauch all came out to discuss the finale with Colbert.

“That wasn’t an easy feat,” Cuoco remarked on how the writers left the characters. “We had a lot of anxieties about how this was gonna go,” she added. “Us as actors, the writers, there’s a lot of pressure on how to end this and fan wanted to know what was gonna happen, so it was tough and I think that they did it brilliantly.”

Parsons couldn’t imagine the finale being “divisive.” Then again, he remembers telling one of the “nervous” writers leading up to the final bow, “Look at it this way, you can’t get it right. It’s a series finale. Someone is gonna hate it.”

Robertson also recorded a special acoustic version of the Big Bang Theory‘s theme song (shown above), and the Barenaked Ladies revealed the first song, “Lookin’ Up” (shown below), off their upcoming Faked Nudes: Naked EP.

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• The Big Bang Theory series finale recap: All the highlights from the show’s sweet send-off
• The Big Bang Theory showrunner Steve Holland answers burning questions about the series finale
• Hugs, tears, and cheers — exclusive Big Bang Theory photos document sitcom’s final week