Conan O'Brien, David Letterman Conan O'Brien, David Letterman

Conan O'Brien is heading to Late Night with David Letterman for the first time in 13 years.

It should be an interesting sit-down, to say the least. The two have a lengthy history, as O'Brien took over Letterman's Late Night spot in 1993. They also have a shared history involving fellow late night host Jay Leno. In 1992, Leno was hired to take over The Tonight Show from Johnny Carson — a gig Letterman had been vying for and the catalyst for Letterman's exit from NBC.

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