If you’ve watched Conan O’Brien’s shows or Late Night with Stephen Colbert, you’ve probably seen Brian Stack playing a wide range of characters, including Frankenstein and one of the Slip Nuts. He’s been a writer and performer for both shows, which has meant running across a huge number of famous people. Here, Brian counts down his top five celebrity encounters to lull you to sleep. Doze off to dreamland hearing about awkward conversation with Walter Cronkite and relationship advice from Mötley Crüe.