Ashton Kutcher and Sean "Diddy" Combs recall how their rat pack was formed when Diddy gave Ashton a call when he learned an episode of "Punk'd" was in the works. And how that led to Ashton inspiring Diddy to run the New York City marathon.

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Each week night, THE LATE LATE SHOW with JAMES CORDEN throws the ultimate late night after party with a mix of celebrity guests, edgy musical acts, games and sketches. Corden differentiates his show by offering viewers a peek behind-the-scenes into the green room, bringing all of his guests out at once and lending his musical and acting talents to various sketches. Additionally, bandleader Reggie Watts and the house band provide original, improvised music throughout the show. Since Corden took the reigns as host in March 2015, he has quickly become known for generating buzzworthy viral videos, such as Carpool Karaoke."