By John Dodge

CHICAGO (CBS) — In his first day back on the “Late Show” since the death of Robin Williams, David Letterman delivered a poignant and entertaining tribute to the comedic icon, whom Letterman had known for nearly 40 years.

Letterman told the story their days together as aspiring entertainers, along with the likes of Jay Leno, Elayne Boosler and Tom Dreesen, at The Comedy Store.

It was the first time the late night host saw Williams’ act, and it was so revolutionary and insanely funny that Letterman figured his career was over, resigning himself to a life in his home state of Indiana.

“We were morning dew,” Letterman said. “He was a hurricane.”

During the 10 minute segment, Letterman shared a photo of himself, Williams and Richard Pryor (two of them were funny and the other was not, he quipped) and played a montage of Williams’ appearances on the show.

Perhaps the best of the nearly 50 appearances was the time Williams appeared on set dressed as a surgeon, right after Letterman had returned to the show after heart bypass surgery. During the classically frenetic bit, Williams pulled off his mask and joked about actually doing the procedure.

In closing the tribute, Letterman, his voice somber, tells his audience he had no idea Williams “was in pain.”

Williams, 63, committed suicide last week and was found in his California home.

Despite his enormous success as a comic and actor, he had been struggling with depression for years and was suffering from the early stages of Parkinson’s disease.

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