Shirtless Seth Rogen and James Franco Surprise Jimmy Fallon on His B-Day!

The Tonight Show Starring Jimmy Fallon staff pulled out all the stops to give Jimmy a 40th birthday to remember on Friday. The hilarious celebration started right after Jimmy told the audience he was expecting a "special guest." He was admittedly confused when a giant birthday cake was revealed, only for a shirtless Seth Rogen to pop out with a sea of balloons. And that was just the warmup! It wasn't long until James Franco and an iconic musician gave Jimmy even more laughs. Check out the video above, and then get nostalgic with a retrospective of Jimmy's early career and all the times he's nailed it with classroom instruments and music superstars.

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