David Letterman marked his return from vacation with a moving tribute to his friend Robin Williams.
Letterman stated on the Late Show with David Letterman, "It was just a pleasure to know the guy and he was a gentleman and delightful. I had no idea that the man was was in pain and suffering."
Letterman has known Williams for 38 years. He recalled the time Williams asked him to appear on Mork & Mindy when he was an unknown comic.
"He gave me a job!" said Letterman.
Letterman then played a montage from Robin Williams' fifty appearances on his show.
Another colorful character has a special connection to Robin Williams. He's the physician Robin Williams portrayed in the 1998 movie Patch Adams, a larger-than-life figure who believes laughter is the best medicine.
Watch INSIDE EDITION's Interview with the Real Patch Adams
"He was loved. What I loved about Robin, I lived in his house, I was with him a lot during the filming and he was always gracious and kind and considerate and thoughtful." said Adams.
When Williams committed suicide last week, Adams was in Peru with his Gesundheit Institute, which uses clowns to help relieve people's suffering. His first interview since returning to the USA was with INSIDE EDITION.
"People would tell me, school teachers or mechanics, would say 'I come home. I've had a rough day, I put in Patch Adams for five minutes and I feel better,'" said Adams.
Adams says Williams' work in the movie has had an extraordinary impact around the world.
"He was a giver of hope. I have 50,000 letters from people who said, 'I saw the movie and I went into medicine and I'm now working in Africa.' One of those would be legacy enough and I have thousands upon thousands of those letters," said Adams.
And a touching YouTube tribute to Williams has gone viral. The video uses Williams' speech from the movie Jack with scenes from some of his other pictures.
Its ending will break your heart. "Make your lives spectacular. I know I did," recites Williams in one of his many film appearances.