Video: Justin Timberlake, The Roots & Jimmy Fallon "History of Rap Pt. 2"

When Jimmy Fallon and Justin Timberlake did this the first time, it was a huge hit. Now they're back to cover more hip-hop songs from the likes of Kurtis Blow and Grandmaster Flash to Rick Ross and Lil Wayne. With The Roots backing them, this is worth the watch.