Jimmy Fallon started his first week on the Tonight Show with "The Evolution of Hip-Hop Dancing" (with help from Will Smith) and finished it with "The History of Rap."

Actually, it was a pretty safe bet (well, safer than that "Loser keeps Bieber" wager over the USA/Canada hockey game, anyway) that Friday's visit from Justin Timberlake would end in the fifth edition of "History of Rap."

Among the songs covered this time:

LL Cool J, I'm Bad

Run DMC, Beats to the Rhyme

Crazy Calls Answering Machine commercial

Beastie Boys, No Sleep Til Brooklyn

Positive K, I Got a Man

Notorious B.I.G., Big Poppa

Snoop Dogg, Woof

Tone Loc, Wild Thing

Will Smith, The Fresh Prince of Bel-Air Theme

Warren G, Regulate

NWA, Straight Outta Compton

Ini Kamoze, Here Comes the Hotstepper

Outkast, So Fresh, So Clean

Kriss Kross, Jump

Skee-Lo, I Wish

Jay Z, 99 Problems

Ludacris, Move (Expletive)

Drake, Started From the Bottom

Kendrick Lamar, Swimming Pools (Drank)

Kanye West, Good Life

Run DMC, Walk This Way