Oprah: Now let's talk about how you got started in comedy. When did you realize you could make people laugh?

Tina: Around sixth grade. The only way I could get comfortable around people was to make them laugh. I was an obedient girl, and humor was my one form of rebellion. I used comedy to deflect. Like, "Hey, check out my zit!"—you know, making fun of yourself before someone else has a chance to.

Oprah: I'm surprised at something you've admitted about your high school days: You were mean to the point of being caustic. I know you were in the movie Mean Girls —you actually adapted the book it's based on—but I wouldn't have guessed that you were mean yourself.

Tina: It was about lashing out at others to make myself feel better.

Oprah: Why were you lashing out?

Tina: It was the kind of thing where if I liked a boy and he liked some other girl, then that girl was in trouble.

Oprah: You were one of those girls!

Tina: Yes—in my circle of loser friends. I don't think I ever truly bullied anyone; it was about jockeying for position and trying to take the attention off myself. But that's a dangerous habit for girls to get into.

Oprah: If this were The Oprah Winfrey Show, I'd be asking if there was anyone you wanted to apologize to...

Tina: Well you know, when I wrote Mean Girls, I had some archetypes in my head—like the prettiest girl and the most popular girl. And as I was working on the script, I threw in some names of real people from high school and mixed them up with other random names. I later heard from a friend who went to my high school reunion that some of my former classmates weren't pleased. When they saw the movie, they were like, "What did I do to her?" I was inadvertently hurtful. So I apologize to the women whose names I used.

Oprah: Okay. Changing the subject now: At the University of Virginia you started as an English major and then switched to drama.

Tina: Yes, I studied playwriting and acting, but somehow I knew that serious acting was not really quite what I was intended for.

Oprah: And when you moved to Chicago in 1992 to do improv at Second City, did you know you'd found your calling?

Tina: Yes. In Chicago improv is a cult. Everyone who's in it is so into it—all you do is go out four or five nights a week and watch other people improvise. I can't think of anything else like it.

Oprah: It's its own art form.

Tina: It is. And when people try to televise it, it shrinks. The thing that comes closest is free-form jazz. Sometimes when you listen to a recording, you're like, "This is quite long," but if you're there hearing it in person, it's so exciting.