Watch Justin Timberlake and Jimmy Fallon Open 'SNL' 40th Anniversary Show

Jamie McCarthy/NBC
Jimmy Fallon and Justin Timberlake walk the red carpet at the SNL 40th Anniversary Special at 30 Rockefeller Plaza in New York, NY on February 15, 2015.

The Saturday Night Live 40th anniversary celebration opened Sunday night (Feb. 15) with Justin Timberlake and Jimmy Fallon rapping about tons of famous SNL sketches over the years.

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The massive three-and-a-half hour event includes more than 100 guests, ranging from Adam Sandler to Zach Galifianakis. On the music side guests include 50 Cent, Arcade Fire, Backstreet Boys, Fiona Apple, Jack White, Jon Bon Jovi, Kanye West, Keith Richards, Ludacris, Miley Cyrus, Paul Simon and Taylor Swift.
Watch Timberlake and Fallon open the celebration in the clip below.