'SNL:' Jimmy Fallon, Harry Styles Lead Flash Mob in 'Let's Dance' Number

Will Heath/NBC

Pictured: (l-r) Vanessa Bayer, Kate McKinnon, Sasheer Zamata, host Jimmy Fallon, Bobby Moynihan, Mike Day, and Aidy Bryant during the "Let's Dance Monologue" on April 15, 2017

Saturday Night Live alum Jimmy Fallon returned as guest host this weekend and, along with musician Harry Styles, led a flash mob to dance to the late David Bowie's hit song "Let's Dance."

"It's so great to be back here on Saturday Night Live. This is where it all started for me. I'm really so happy to come home," Fallon said during his opening monologue. "Tonight is extra special because this is the first time in SNL history that we are going out live coast to coast all across the country and Canada. ... Tonight is bigger than a show. It's a party!"

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SNL guest host Octavia Spencer reprises her role as housekeeper Minnie from 'The Help' in the sketch.

As "Let's Dance" began to play, he urged those sitting in chairs in front of him to follow him down the hall and throughout the building, picking up random people along the way, including Styles.

The stunt ended with Fallon and his followers joining the regular SNL cast members on the show's main stage.

By Karen Butler

Originally published in UPI Entertainment News.