Ariana Grande Joins Barbra Streisand Onstage For Surprise Disco Duet!

Ariana Grande surprised Barbra Streisand fans when she jumped on the stage to perform with the legendary actress and singer.

The "Thank U, Next" songbird got down to disco while singing with Streisand on Tuesday during her show at the United Center concert in Chicago.

Holding hands and embracing each other, they belted out Streisand's 1979 classic with Donna Summer, "No More Tears (Enough Is Enough)."

Unsuspecting fans lost it when Grande appeared from backstage dressed in a black suit.

FYI -- Grande was born 13 years after the song hit the airwaves.

Barbra Streisand shared an adorable picture with the 26-year-old backstage after their surprise performance and the duo looked close like friends.

"Secret’s out," the legendary singer captioned the shot, adding a big "thank you" to Grande.

The "Boyfriend" songstress reciprocated the love, posting the exact same picture and writing that she's "cherishing this moment forever."

Interesting enough, Streisand's duet with Grande comes days after Mariah Carey came to her show.

She didn't have Carey perform, but the "Always Be My Baby" singer posted a snap of them backstage from her Saturday concert and called Streisand "A LEGEND."

She also had Hillary and Bill Clinton in the audience for the same show.

Streisand posted a photo with the political powerhouse couple and wrote, "So honored this brilliant couple attended my concert in New York."

She also gushed over Clinton banning assault weapons during his presidency.

"The only President in the last 50 years to leave our country with a budget surplus. He also banned assault weapons, which the Republicans then overturned," she added.

Streisand is currently on tour through December.