Fallon punks The Roots with 'Shades of Grey' video

Questove of the Roots reacts to a hideous face prankishly inserted by Jimmy Fallon into a "50 Shades of Grey" movie trailer.

Tonight Show host Jimmy Fallon had a little fun at the expense of his house band, The Roots, whose roots, of course, are in Philly.

Fallon taped the reactions of band members as they watched the viral new trailer for 50 Shades of Grey, a much-anticipated flick based on the kinky-sex bestseller. 

But Fallon went further, to guarantee reaction.

"You know those scary faces that can sometimes pop up in YouTube videos? We added one," he said while introducing the video, which, as of Thursday morning, had gotten a half-million views.

Here's the 50 Shades of Grey trailer:

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com.