​Lady Gaga and Tony Bennett perform surprise duets at the Montreal Jazz Fest

Lady Gaga is full of surprises, but no one expected to see the Art Pop diva on stage with Tony Bennett at Montreal’s Jazz Fest on Canada Day.

The 28-year-old singer premiered a few songs from the duo’s forthcoming album titled Cheek to Cheek, a compilation of duets that’s been in the works for almost two years.

Surprise ambushes are starting to become a thing for this pairing, as Lady Gaga and Tony made a similar appearance on the last day of classes at the Frank Sinatra School of the Arts last month.

Of Gaga, the legendary crooner said in June, "When I first heard Gaga sing, my reaction was that she is going to be bigger than Elvis."

He added, "She is so bright and intelligent and she has it. In jazz, you either got it – the syncopation, the rhythm – or you don't, and when I heard Gaga, I said, 'She's got it!'"

In Montreal, the twosome sang go-to jazz tunes like “But Beautiful” and “Lush Life,” and she also reportedly told the crowd that Cheek to Cheek “will be the end of the beginning of my career.”

After the surprise show, Lady Gaga took to her Instagram, writing, “I had the time of my life tonight.”

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