Roots co-founder Questlove is back at Sundance after winning an Oscar for Summer Of Soul, this time the musician is looking at Sly Stone to see today.

Questlove's documentary, Ladies & Gentlemen... 50 Years of SNL Music, highlights the show's most iconic musical performances and comedy sketches — and addresses the show's "unhummable" theme song.

It's a mashup of performances from artists that few people would think of putting together, like R.E.M. and Morris Day, Rick James and Duran Duran, Hanson and Cher. Filmmaker Ahmir “Questlove” Thompson's experience as a DJ taught him enough about beats per minute and musical keys to meld things seamlessly.

Born Ahmir Khalib Thompson on this day in 1971, Questlove celebrates his milestone birthday today. Known as the iconic drummer for the legendary hip-hop band The Roots, Questlove’s impact on music and culture extends far beyond the stage.

Barbara Hernandez (Drew Barrymore), Dave (Jimmy Fallon), Virginia Klarvin (Rachel Dratch), Roger ... 50 Years of SNL Music, a documentary about SNL's Musical Guests that's co-directed by Questlove and Oz Rodriguez, airing on NBC January 27.

An Oscar-winning documentary that premiered at the Sundance Film Festival four years ago got a shoutout during one of the latest episodes of “Pop Culture Jeopardy!” During episode No. 19 of the new series,

"Jimmy stepping into his destiny means me talking to you at this moment," said Questlove, whose band the Roots became house band on the “Tonight” show when Fallon took over that franchise.

Questlove's newest documentary features interviews and clips from 50 years of musical performances on Saturday Night Live.

The celebration of SNL’s 50th anniversary continues with a look at their iconic music performances in a feature doc directed by Questlove.