Watch Will Smith, Alfonso Ribeiro’s ‘Fresh Prince’ reunion

Will Smith and his “The Fresh Prince of Bel-Air” costars delighted the audience of “The Graham Norton Show” on Friday with a surprise performance of the ultra-catchy theme song.

“Now this is a story all about how my life got flipped turned upside-down...”

If you grew up in the ‘90s, you probably know how the rest of it goes.

Smith was in town to see his eldest son Trey, a DJ, perform at a London club, where he was joined by his costars, and to attend a few London events with son Jaden.

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Appearing on “Graham Norton” Friday to promote their upcoming sci-fi flick “After Earth,” Smith, 44, and Jaden, 14, teased to the younger Smith’s rap skills. Soon after, Norton prompted the duo to perform.

When Smith, whose rap career segued into acting, last appeared on the U.K. talk show, he broke into the catchy tune and the performance apparently garnered more than 8 million hits on YouTube. So Smith decided to introduce his costar and musical partner, DJ Jazzy Jeff, and recreate that initial magic. The trio performed the rap to the audience’s delight with Norton’s guests Bradley Cooper and Heather Graham dancing along.

But their show didn’t stop there.

Smith then introduced a very special, surprise secret guest: Alfonso Ribeiro, who played his cousin Carlton on the show. Cue Tom Jones!

Smith and Ribeiro broke into Carlton’s signature sideswing and snap dance to “It’s Not Unusual.” The audience cheered like crazy.

Then Norton joined the fun, dancing to the Sugarhill Gang’s “Apache.” You know, the “jump on it” pelvic-thrusting song.

“Just a little treat for you,” Smith said at the end of the high-energy reunion performance.

A fresh treat, indeed! Watch the video above and tell us what you think.

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