"The bar was packed beforehand," said Bridget O'Donnell, an office manager for the Intermezzo restaurant who witnessed the spontaneous, half-hour set. "When they started playing it was just crazy. It's not gonna happen again ever."

The Artist dropped by the eatery around 11 p.m., after taking in a performance by the New Power Generation Dance Company, led by his wife Mayte. "He had dinner, and we closed the restaurant," said O'Donnell. "Stevie Wonder showed up shortly after, and after they were done eating, the two of them got together, came up on the bar stage and decided to play."

Although the former Prince and Stevie Wonder are both versed in numerous instruments, the Artist settled in for a steady ride behind the drum kit, allowing the hometown hero to work his magic on the keyboards and microphone. Joining the pair was another funk originator, Larry Graham, former bassist for Sly and the Family Stone, and a familiar face on Prince's current Jam of the Year tour. Rounding out the all-star pick-up band were Tony Rich and the NPG's Kat Dyson.

As the ensemble romped through Wonder's "Superstition," restaurant managers locked the Intermezzo's doors to the throngs that were gathering on the sidewalk. Wonder then led the group through Sly and the Family Stone's "Thank You Falettinme Be Mice Elf Agin" and "I Want to Take You Higher," as well as a new song Wonder penned off the top of his head.

"It was totally crazy," said O'Donnell. "The people who were there to see it were just ecstatic. It was totally amazing! The first thing I did was call my mom and tell her she had to come down." -- Chris Nelson