Robert De Niro, Lady Gaga, Tina Fey + More Owe Jimmy Fallon $100 - VIDEO

Jimmy Fallon began his stint on The Tonight Show last night (Feb. 17) and while there he reminded a buddy of his they owe him $100 for betting he would never be hired as host.

Enter a cavalcade of guest stars to hand over some Benjamins to a bewildered Fallon.

The surprise guests in question included Robert De Niro, Tina Fey, Joe Namath, former mayor Rudy Giuliani, Mariah Carey (who acts about as good as she did in Glitter), Tracy Morgan, Joan Rivers (whose hasn't been on the Tonight Show since being banned over 30-years ago), Kim Kardashian, Seth Rogen, Lindsay Lohan, Sarah Jessica Parker, Mike Tyson and Lady Gaga.

Stephen Colbert hilariously arrived to finish off the segment, with a bucketful of 10,000 pennies, the instinct to snap a selfie and the proclamation: "Welcome to 11:30 bitch!"

Welcome to 11:30 indeed!

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