"As I pulled up to the theatre, I heard the news, so now I was stunned, and 20 minutes later I’m on the stage with him. We had a ball. It was really fun, and I’m really happy for him… bittersweet feelings. After 34 years of broadcasting, Dave is an iconic comedian to us and a contemporary who broke down a lot of barriers of late-night when it was his time... It’s not easy to say goodbye to people you really care about." Funnyman Billy Crystal was one of David Letterman's first guests after the late-night host announced he'd be retiring in 2015. Crystal was also Jay Leno's final guest when the TV veteran signed off from The Tonight Show earlier this year (14).