Zinoman says Dave was constantly miserable — even when his show was No. 1 in the ratings! When he was passed over to replace the retiring
Johnny Carson on 'The Tonight Show' in favor of
Jay Leno in 1993, Letterman took his act to CBS where he was offered 16 million a year. Even after proving his worth by consistently topping Leno in the ratings, he remained gloomy and grumpy. A former producer recalled when a then-popular
Mel Gibson was booked as a last-minute replacement to fill a spot on the show, Dave turned his nose up at him — instead choosing to interview show regular
'Kamarr' The Discount Magician!