Will Smith / Facebook 1 / 11
Will Smith / Facebook 1 / 11

The Fresh Prince of Bel Air may have moved zip codes, because Will Smith was the prince of Las Vegas on Aug. 15.

The "Focus" star headed to Sin City on Friday to see his son, Trey Smith, aka DJ Ace, perform at the Palms Pool. Turns out, Smith, himself, ended up doing a little performing.

Longtime Smith friend DJ Jazzy Jeff followed up on the turntables after DJ Ace, and that's when the Fresh Prince sprung into action.

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"He watched Ace for a while without anyone knowing he was even there," a source said. But after DJ Jazzy Jeff began deejaying, Smith came out on stage in full view of the crowd of bikini'd women and muscled men and performed his early 90s hit "Summertime." In the middle of the song, Smith doffed his shirt, showing a chiseled physique.

"We haven't been on stage in forever," he said of he and longtime music partner Jazzy Jeff. "It's been seven months."

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Over the course of the day, Smith performed two other songs, including the "Fresh Prince of Bel Air" theme song.

"The crowd was going nuts," the source said. "He was singing and going crazy. He was dancing hard. As soon as he saw (DJ Jazzy Jeff) they did this crazy dance and they started taking selfies."

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At the pool with Trey's mother, Sheree Fletcher, Smith signed several autographs and even jumped into the crowd, but security teams quickly rescued him from the throng of people clamoring to get near the box office star.

Following the mini concert, Smith and his party of seven headed to N9NE Steakhouse, where they dined on an oversized seafood tower and steaks. Afterward, Smith signed Chef Barry Dakake's famous office door, which has been signed by thousands of other celebrities.

And if you think Trey Smith was embarrassed that his father performed old songs and paraded around stage shirtless, think again. Following the day's activities, he tweeted, "Thank You!!!! @PalmsPoolLV Today Was Incredible. You Guys Are Awesome."