To close out the inaugural week of The Tonight Show Starring Jimmy Fallon, the host enlisted his long-time friend and incredible comedy collaborator Justin Timberlake as the episode's sole guest. Jimmy Fallon and JT reinvigorated their Late Night franchise The History of Rap for its fifth (fifth!) installment (but call us when it includes "Danny Glover") and rehashed their shared sketches on SNL, as well as improvised new bits. Fallon is genial on his own, but Timberlake truly brings out the best of him.

Watch The History of Rap Part 5 above and or watch the whole episode below.

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