Lady Gaga's Monster Ball is back in her native New York for a pair of sold-out shows at Madison Square Garden, and some of the biggest stars in the world are showing up to party with Mother Monster.

Paul McCartney and Michelle Pfeiffer were among the more than 20,000 fans who turned up to catch the last leg of Gaga's years-long tour, which Billboard estimates will likely cross the $200 million mark in grosses by the time it concludes in early May.

Rumors are also swirling that, ahem, Madonna was in the house, which would certainly put to rest talk of bad blood between the two singers after Gaga's latest smash, 'Born This Way,' was accused of ripping off Her Madgesty's 'Express Yourself.'

While we assume everyone in attendance had a blast, the former Beatle seems to be a bona fide Little Monster and was caught on camera dancing during the show.