Steve O’Donnell has written for David Letterman, Chris Rock, Jimmy Kimmel, Seinfeld, and The Simpsons. Mark O’Donnell has written many books and plays, including the novels Getting over Homer and Let Nothing You Dismay. He won a Tony as the co-author of the musical Hairspray. This interview was conducted over the phone, with Mark in New York and Steve in Los Angeles, shortly after their mutual fiftieth birthday.

STEVE: Why don’t we begin by asking crassly and blatantly why anyone would care to read this interview? I guess there may be some interest in show business, in which we are involved in a… not visible way.

MARK: I like to joke that my autobiography will be called My Life near Show Biz.

STEVE: Yes, we’re in the vicinity—though perhaps, like the underground tunnels that connect the worlds of Disneyland or Disneyworld, we’re like anonymous costumed cast members shuttling from one enchanted castle to another ride, like Pirates of the Caribbean. Let’s also be frank about the freak-show angle about our twinness, though I have to believe that even that alone isn’t quite enough to sell it. There are other twins who’ve exerted some fascination in show business and much more famously, such as Mary Kate and Ashley—and by the way, we should figure out which of us would be Mary Kate and which of us would be Ashley later.

MARK: Philip and Julius Epstein—

STEVE: The guys who wrote Casablanca. There was some other guy involved, but he was just a “uni”—that is, a non-twin.

MARK: The Sklar brothers… Well, you’ve won, what? Four Emmys? Five?

STEVE: Well, I like to think of myself as a sixteen-time Emmy loser. It just keeps me more humble. Yes, I was lucky enough to garner a few statuettes because of the outstanding reputations of Dave Letterman and Chris Rock, whom I’ve worked for. But there are other twins who are arguably more interesting than you and I. The Hee Haw twins—the Hager brothers, Jon and Jim, who I believe still perform. Perhaps they still pick and perhaps they still grin.

MARK: I was overseas, in Ireland, when Hee Haw was in its heyday, so I don’t know the Hager brothers.

STEVE: You got to meet one of the Shaffer brothers, didn’t you?

MARK: Right, Peter and Anthony Shaffer, the twin playwrights—Amadeus, Sleuth, Equus.

STEVE: I guess I think we should get to the more sensational aspect of our relationship—the fact that we’re twin brothers from a large family of ten brothers and sisters, working-class Cleveland, offspring of a welder and a… homemaker, who were themselves the offspring of immigrants. And, that most profound...