Conan O’Brien (June 2009 to January 2010)
Conan, the host of NBC’s 12:35 a.m. “Late Night” show, made it no secret that “Tonight” was his end-game. To keep him from leaving for another network when his contract was up in 2004, NBC made him a promise: He could have “The Tonight Show” . . . in five years. Jay Leno agreed to go along with this plan and retire. In June 2009, Conan officially took over, and ratings dropped, and started consistently losing to Letterman on CBS for the first time in years. Meanwhile, Jay Leno’s new five-nights-a-week prime-time show at 10 p.m. resulted in disastrous ratings. NBC officials came up with a new plan – they would shift Leno to 11:30, bumping “The Tonight Show” to 12:05. Conan balked, then walked, taking a $40 million exit package and eventually moving to TBS, where he still languishes today.