PASADENA, Calif.--Robin Williams and HBO are sort of old friends.
He first appeared on the pay-cable network almost a third of a century ago--in the 1977 "Young Comedians" special. He co-hosted nine "Comic Relief" events on HBO. And he did solo, stand-up specials in 1978, 1983, 1986 and 2002.
This weekend, he's back. "Robin Williams: Weapons of Self-Destruction" airs Sunday at 10 p.m. on HBO.
"After having open-heart surgery, it's going to be very interesting. Especially with a cow valve," said Williams, 58, who underwent the procedure earlier this year while he was in the midst of the "Weapons of Self-Destruction" tour. "It's going to be this idea of--can I do the hour and a half, the long program."
(Sunday's special was filmed in November in Constitution Hall in Washington, D.C.)
And he promised he would talk about his heart surgery.
"Yeah, the details of the surgery are there," he said. "I mean, it was interesting that I had the surgery at the Cleveland Clinic. And I woke up going, 'Where am I?' And they said, 'Cleveland.'
"And I kept going, 'Why?'"
Appearing before TV critics, Williams was in the room watching a clip-reel of his 32 years on HBO. And, it appeared, he was a bit taken aback by it.
"It's interesting. I realize I need more therapy," he joked. "It's wild to see stuff from 30 years ago and go, 'Wow, that's so long ago.' And to realize, 'Yes, I'm not dead, but yet they're showing a clip reel.'
"And it's pretty strange to see the transition over the years and to see that it kind of marks different time periods. Like the one in Vegas was after getting out of rehab.
"I realize it's been a long time. But HBO has always been there. That's why I came back."
If it were possible, would 2009 Robin Williams have any advice for that goofy, 1977 Robin Williams in the rainbow suspenders?
"Brace yourself. It's going to be a long run," he said. "And it's going to be an interesting thing. It's been a roller coaster.
"The reason I'm going back to do stand-up again is I've run out of the merchandising money from 'Bicentennial Man,'" he joked.
Williams said he has no second thoughts about where his career has taken him. Not even when it comes to some of his much maligned movies, like "Bicentennial Man." Or "Patch Adams."
"Oh, no regrets, no," he said. "That's a very popular movie with people who have been in hospitals.
"You know, there's some who go, 'Not everything worked, but at least it was interesting to try.'"
Williams said his greatest personal achievement is his three children.
"All of them astonish me," he said. "I'm not the world's greatest dad. I'm a work in progress. But I'm so proud of them."
His oldest son, Zak, 26, graduated from New York University with a degree in linguistics, "which made me think he was going to open up a poetry-repair shop."
His daughter, Zelda, 20, is an actress who has been "doing mainly horror movies, which is always great. 'We loved it when you got slashed. It was so good.'
"And my other son [Cody, 18] is studying poetry and literature and art history. To me, that's the ultimate production deal."