But before he faces his TV audience, O'Brien confronts his demons on air Wednesday night when he and Dr. Phil McGraw host a CBS primetime special about substance abuse and living sober.
The Early Show co-anchor Julie Chen spoke with the tough-talking therapist about the challenges facing O'Brien.
Asked if he tiptoed around some of his questions because O'Brien is a celebrity himself, Dr. Phil says, "To me, a junkie's a junkie. And an alcoholic's an alcoholic."
O'Brien admits to Dr. Phil that his behavior was out of control. And to Chen he says there was a lot of tough love in that interview: "With Phil, it's really therapeutic. And I think you'll see that it was not only therapeutic, it was honest; it was tough. I even squirmed a little bit during this interview."
For years, O'Brien cozied up with celebrities while reporting on the stories behind Hollywood's headlines.
But in March, he found himself in the direct glare of the spotlight when a slew of sexually explicit voice-mails from O'Brien became public.
Here is an excerpt: "I want to (bleep) go crazy with you. I want to talk dirty to you...get another woman up...Let's get crazy, get some coke."
Quizzed by McGraw, O'Brien says that is not him, but admits it is his voice.
"What was going through your mind that said this is OK, I'm going to do this not once, not twice, but 7 or 8 times?" Dr. Phil asks him.