Grammys 2015: Surprisingly rowdy vibe envelops Clive Davis gala

“Tonight,” promised Clive Davis, “is going to be off the hook.”

That’s how the 82-year-old record executive welcomed celebrities and power players to his annual pre-Grammy gala Saturday at the Beverly Hilton.

And though Davis is no stranger to hyperbole, there was something especially wacky about this year’s edition of the all-star bash, which on more than one occasion found various A-list superstars grabbing for the microphone like somebody’s drunk uncle at a wedding.

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The party – with a guest list that included Joni Mitchell, Magic Johnson, Kenny G, Herbie Hancock, Taylor Swift and, at the same table, Nancy Pelosi and Lana Del Rey -- began politely enough as Sam Smith, typically dapper in a gray Armani suit, crooned “My Funny Valentine” and his Grammy-nominated “Stay with Me” to wine-bar piano accompaniment.

It was pretty, of course – and pretty boring.

But then Smokey Robinson came onstage trailed by Miguel, Aloe Blacc and JC Chasez, who launched into a bouncy rendition of “My Girl” that inspired Jamie Foxx to leap from his seat in the audience and sing a few lines. After he finished, Foxx passed the mic – hey, why not? -- to Philip Bailey of Earth, Wind & Fire.

Mary J. Blige turned up next to join Robinson for a silky “Being with You,” which brought the room’s energy back down to a comfortable schmoozing level. On her own, though, Blige powered through her song “Doubt” with the kind of full-on emotional intensity you rarely see at an insiders’ event like this.

Later, Blige pulled a Jamie Foxx during Carole King’s brief set, jumping to the stage to do a bit of “You’ve Got a Friend” then roping in John Legend to add his 2 cents.

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King and Legend, the latter of whom also performed “All of Me” and a snoozy duet with Meghan Trainor, were two of several songwriters in the house to pay tribute to Martin Bandier, the Sony/ATV Music Publishing honcho who received the Recording Academy’s President’s Merit Award.

Yet Bandier’s own moment in the spotlight – for an acceptance speech in which he declared that “songwriters are not being adequately compensated for their creations in today’s digital world” – was delayed when some in the audience demanded that Pharrell Williams follow up a slick rendition of Daft Punk’s “Get Lucky” with “Happy.”

Whether or not it was truly spontaneous (the ragged result surely sounded it), the song was another unexpected jolt in an evening typically known for its smooth civility.

Not that there wasn’t plenty of that, first from Johnny Mathis – who more or less floated through “It’s Not for Me to Say” and “Chances Are,” his high, delicate voice as pillowy as it was a half-century ago – and later from Barry Gibb, who closed the three-hour show with a gorgeous “To Love Somebody.”

But even these career softies caught some of the party’s surprisingly rowdy vibe when each was cheered like he was a member of One Direction.

They turned the drunk uncles into squealing kids.

Twitter: @mikaelwood