For much of his life, Mike Tyson could crush, pummel and otherwise destroy anything in his way. He didn't need to do much explaining. But in recent years, rather than block out his emotions and his roller coaster past—which includes stints in prison and rehab—the former heavyweight champion has been facing both in a brutally honest fashion.

Former heavyweight champion Mike Tyson, whose one-man Broadway show begins July 31, spoke exclusively with The Wall Street Journal in his room at the Ritz-Carlton Battery Park. Bryan Derballa for The Wall Street Journal

In the spring, Mr. Tyson launched a one-man show at the MGM Grand Hotel & Casino in Las Vegas, opening up about his extreme highs and lows. Now he's heading to Broadway under the guidance of director Spike Lee: From July 31 to Aug. 12, Mr. Tyson will deliver "Mike Tyson: Undisputed Truth," a one-man show at the Longacre Theater.

The show is in some ways an extension of his second career as a budding comedian; he's made appearances on late-night talk shows, foreign variety shows and "The Hangover" franchise. Currently in rehearsals for his Broadway run, Mr. Tyson, who is 46, took a break to describe how he's preparing for the theater and how his career is evolving—along with a touch of motivational how-to.

Live theater is so much about emotion. What do you hope people feel when they watch your show?

I don't know what anyone feels. But I know once I get started, I connect with them. I can tell when this part comes and it's not going to be healthy for me, I know they're going to feel the pain from that. When it's funny stuff, and I'm a jerk and I'm humiliating myself, they'll see the irony in that and laugh even though it's tragic. It's a roller coaster of emotion. I'll be pretty raw up there. I'm naked. Not actually naked. Emotionally naked.

'I'll be pretty raw up there. I'm naked. Not actually naked. Emotionally naked.' Bryan Derballa for The Wall Street Journal

You opened yourself up to the public a few years ago in James Toback's documentary, "Tyson."

I'm filming that in rehab so I'm mixed with emotion and probably still high. I probably still had stuff in my system. But I'm conscious of what I want to say because I'm emotional about it. Really, that was some dark s—.

Will you go back over some of that same territory in the new show?

Absolutely. But now I have characters. I'm not just talking about [trainer and mentor] Cus [D'Amato]. Cus always said to me, "In order to be the best, you need to do what you hate to do, but do it like you love it." But I'm not going to say it like that; I'm going to say [delivers the same phrase in a gruff accent.] I have to make sure my throat doesn't crack. As a kid, I had a really high-pitched voice, and I hated my voice, so I smoked a lot. I read that some entertainer smoked a lot and their voice got heavier, so that's why I smoked a lot.

How are rehearsals going?

When I'm rehearsing, this is my crutch. [Holds up binder with script.] I could do it. Then [Mr. Lee] said, put that down and now do it. Pow! When I'm rehearing, it keeps me from getting emotional. Just holding it. I can only perform when it's show time without the script. When I'm in there, and I'm dealing with the emotions, that's why I have to rehearse it, because I have to put the emotions in check before I go onstage.

Do those emotions help your performance?

I'm a really emotional guy. I'm a child when it comes to my emotions. I lived my life as a child through this whole ordeal of life I was living. I wasn't even developed. So that's why I respond the way I do [in the boxing ring]: "The hell with you. Up yours! That's why I still got the belt you guys don't!" I was trying to explain to Spike, when it's show time, It works. I don't know how. I don't know why it works. It just works. Everything is on the line. If I fail, I'm humiliated. I'm dead. I can't work in this town no more. Which is not true, but boom, that's what I feel.

'I don't picture myself as a funny guy. This is a new thing. I think I'm dark.' Bryan Derballa for The Wall Street Journal

So it's a competitive feeling.

Yeah, I don't like that feeling sometimes. My competitive feeling is right up in your face. I'm the best. Don't even try to challenge.

Do you have an awareness of the people in the theater?

Not in the crowd. When I was fighting I did. Maybe now I'm just focused on the art and generating the self. Maybe in time I will be. I don't see nobody but the lights and their silhouettes.

Does it make you feel good to deliver a good joke—like landing a clean punch?

I don't picture myself as a funny guy. This is a new thing. I think I'm dark. I used to take myself too seriously when I was fighting. Funny is not complimentary in the world I came from. I've learned to be a human being. I'm pretty domesticated.

It was a fun surprise to see you turn up in the "Hangover" movies. It really worked.

People say I'm a comedian. People in the field say, "You're one of the up-and-coming new black comedians." I say, "You think so?" I don't look at myself in that perspective. I'd like to do movies like "Dead Presidents" and "New Jack City." I'm fortunate to be a black entertainer, and to be new in the field, and be mainstream.

Your voice is instantly recognizable. Have you taken any voice lessons?

Oh, yeah. I know all these friends who I'm realizing that all these years, they may have been too afraid or didn't want to hurt my feelings to tell me, "Mike, you need an interpreter. I really don't know what the heck you're talking about." No one ever told me that.

There's a clip on YouTube of you singing "The Girl From Ipanema" on Brazilian TV. It's really good!

You know what I would have thought about that guy five years ago? He's a p—. I would have been saying all that stuff just to be negative. I'm so gratified that I can come to this level and not be so serious. I was so insecure, that I wanted people to take me serious. My mentor, Cus D'Amato was a mean old man, a beautiful man, but just wasn't that emotional. That's how I was. I wanted everybody to be afraid of me. Back then that was great. Now it's about nurturing and caring about people less fortunate.

Did you take singing lessons?

No. Mostly with the singing, that's from a comic perspective, because I'm a horrible singer, of course. But people from different countries think I'm great. I sang at an all-girls concert in Brazil. I sang another song in Italy and I had to sing in Italian. I memorized it.

If you had to convince people to come see your show instead of another Broadway show, what would you say?

What makes this unique and different is that it's me up there. It's not no one imitating me. It's not someone saying what I said. It's just me telling it to you in a more articulate but still gritty form.

Do you improvise at all?

I want to improv. I'm in New York. I want to improv and I want to think about using some profanity. What we first used was very light profanity, but we're in New York and I want to get gritty. I have to be totally objective. I might make you laugh but I might be humiliated by stuff. Everything is about the art now

When you're preparing to go onstage, is it similar to preparing for a fight?

Pretty much. I think about all the people who performed on Broadway before me. Burt Williams. Al Jolson. Eddie Cantor. Sammy Davis. I think, my name is with the greatest who ever lived. I want them to mention my name when they mention those guys, too. In order to achieve anything, even to be Mike Tyson, I'm not going to accomplish what I accomplish being "Mike Tyson Big Bad-Ass Black Guy from Brooklyn." No, that's not it. I have to look at myself as greater than I actually am. I'm a god. I'm invincible.

Is that what got you into the ring—to tell yourself "I'm the best"?

You can't just learn by saying it. You have to know you're the best by accomplishing what you've said. When I used to run, I used to run up this mountain. Sometimes the pain would come because I would run really fast. I would say, I beat you every day, why is today going to be any different?

Write to Pia Catton at