"If you came here tonight for sex with a talkshow host, you're in the wrong studio," Leno told his audience in his opening monologue.

In 2005 Letterman was the victim of a planned plot to kidnap his son, then 16 months old, and his nanny in 2005. In that case a house painter who worked for the star had wanted to extort $5m from him.

SHOOT: What's that saying, the joker's wild, and it never rains, it pours...

clipped from www.guardian.co.uk The sharp-witted late-night TV star, who regularly skewers the foibles of other celebrities, found himself on the end of the same treatment after being at the centre of a bizarre blackmail plot over the sexual affairs he had with younger female staff members. Leno was joined by another TV show host, Jimmy Fallon, who cracked: "There's a new book out called Why Women Have Sex that has a list of the 237 reasons why women have sex and Letterman knows the top 10." Meanwhile, Bill Maher on HBO joked: "I've never had sex with members of my staff – the guests, yes, of course, but not the staff." Despite his high profile, Letterman has always tried to avoid being in the spotlight personally. He is often portrayed as the classic "serious clown" whose intense, driven private personality is at odds with his public image as a jokey, happy-go-lucky talkshow host. In another incident, a woman repeatedly stalked Letterman and eventually committed suicide in 1998.