WATCH Will Smith Raps “Fresh Prince of Bel-Air” Theme Song on “Ellen”

Will Smith made an appearance on "Ellen" Tuesday to promote his new movie "Focus" (in theaters Friday), in which he plays a veteran con artist opposite Margot Robbie, and aside from telling Ellen DeGeneres that he doesn't think he's sexy, the actor rapped a few nostalgic hits with the audience.

During commerical break, Smith took it back to the '90s by rapping the famous intro song to his sitcom "The Fresh Prince of Bel-Air," but also put the crowd to the test.

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Instead of just rapping everything, he let the audience take over for most parts. They started off strong, yelling, "In West Philadelphia/ Born and raised/ On the playground is where I spent most of my days/ Chillin' out, maxin, relaxin all cool/ And all shootin some b'ball outside of the school..."

But at one point the crowd's memory went blank and it was crickets. Yikes! (We really could've owned this challenge. Oh well, maybe next time.)

It's all good, though. Will wasn't offended and filled in the gaps. He also gave the guests another surprise performance during commerical break, when he got on the mike and rapped his late '80s jam "Summertime." Only thing missing was DJ Jazzy Jeff.

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