Director John Waters. (Jason Merritt/Getty Images)

In 2012, the filmmaker John Waters, behaving as eccentrically as a character in one of his cult movies (“Hairspray,” etc.), left his house in Baltimore and hitched rides all the way to his apartment in San Francisco. He talked by phone about the resulting book: “Carsick” (Farrar, Straus Giroux, $26). This interview has been edited for length.

What made you decide to hitchhike across America?

I guess it was my own version of a midlife crisis. I’ve always looked for adventures. I look to test myself. And I thought this would be a good way to raise my street cred.

What were the people like who picked you up?

I found them much more open-minded than many people would have thought. And more kind than any character I could ever think up. Maybe that’s just the people who pick up hitchhikers. But they were not predictable. The first person was a black single mother. There was a coal miner and a Republican politician. The one policeman who picked me up gave me grief when he saw that I wasn’t hitchhiking aggressively enough: “Shake the sign!” The only thing they had in common was they liked people. They were interested in what was going on in the world. And for some of them, I think it was a little bit of an adventure.

That goes against the image the media portrayal of “middle America.”

What I find the most offensive is the intellectual world using the phrase “Flyover Land.” I almost choke when I hear that. I hate the term “trailer trash,” which I hear people use, which is as racist as the N-word, but it’s acceptable for anybody to say that. I don’t like extreme white people — I think that’s a fair term — but I didn’t have that many extreme white people pick me up. The generosity of the people on the road was striking because most people thought I was a homeless man. They’d see me standing there shaking a cardboard sign and a baseball hat that said, “Scum of the Earth.” That was the stupidest hat to bring — why did I bring that hat? Who’s gonna pick up somebody who’s wearing a Scum of the Earth hat? But they couldn’t really read it going as fast as you do on a highway entrance ramp.

A few people who picked you up at first drove past you and thought, “Wait, wasn’t that John Waters?” then returned to pick you up.

Maybe a third of them. But most people didn’t, which was refreshing. I have to promote my life all the time. I wanted to hear their stories, not mine. Everybody has drama in their life; everybody has an arc. People said to me, “Are you scared?” Never going out of your house — that’s scary to me. Then nothing will happen. Of course, there were times when I was dying to be recognized. After an hour of waiting, I’d be giving a Vanna White-like hand signal to my mustache.

Is life dull if you don’t liven it up a bit?

Life is never dull. I’ve never understood reality television because just walk outside, just watch people. When I would stand there waiting for a ride for eight hours — no, even that wasn’t boring because that was terror. There was real drama going on. I am never bored.

See Jonathan Yardley’s review of “Carsick” in today’s Outlook section.