David Letterman 'Had No Idea' Robin Williams Was Suffering

PHOTO: Robin Williams is pictured in New York City on April 28, 2012. PlayCharles Sykes/AP Photo
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David Letterman has spent the past week thinking about Robin Williams.

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The “Late Night” host knew Williams, who apparently hanged himself Aug. 11 at age 63, for 38 years. Williams and Letterman performed at the Comedy Store in West Hollywood, part of a 1970s stand-up groundswell featuring acts such as Jay Leno, Jimmy Walker and Tom Dreesen.

Initially, Letterman thought Williams was from Scotland. He quickly realized how special Williams was, and that he actually wasn’t from Scotland.

“We’re like morning dew; he comes in like a hurricane,” Letterman said Monday during taping for his show's first new episode since Williams’ death.

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Williams became a star by the late 1970s, appearing on “Happy Days” and the spin-off smash sitcom, “Mork & Mindy.” One of Letterman’s first acting roles – as a smug speaker, Ellsworth – came on “Mork & Mindy,” with Williams helping Letterman secure the spot. The bond between Letterman and Williams was cemented in Williams’ 50-some appearances on Letterman’s late-night shows.

After discussing his friend Monday, Letterman presented a montage featuring Williams’ jokes and laughter. He later reflected on the loss.

“Beyond being a very talented man and a good friend and a gentleman, I’m sorry like everybody else I had no idea that the man was in pain, that the man was suffering,” Letterman said, jabbing the desk with the butt of his pencils.

“But what a guy.”