by Margy Rochlin
THE NEW YORK TIMES 2017

Before he was Kevin Garvey, the tormented police chief he plays on the HBO supernatural drama “The Leftovers,” Justin Theroux appeared on Broadway in “Three Sisters,” wrote the smash movie “Iron Man 2,” illustrated books and helped curate a creepy art installation. “If you’re lucky, you get to live a bunch of lives in one lifetime,” said Mr. Theroux, 45.

None of this career hopping has given him insight into how 2 percent of the world’s population vanished, a question left unanswered in “The Leftovers.” Created by Damon Lindelof (“Lost”) and Tom Perrotta, who wrote the novel the series is based on, “The Leftovers” starts its third and final season on Sunday, April 16. “The go-to theory is that there’s an alternate universe where the people go,” or that they’re still here “but you can’t see them,” Mr. Theroux said. “I haven’t come down on either side because I think the whole point of the show is the exquisite unknowing.”

In Season 3, three years have passed and Kevin is trying to live a normal life in Miracle, Tex., having somehow survived being shot and drinking poison. But with the seventh anniversary of the Sudden Departure looming, Kevin and his wife, Nora (Carrie Coon), head to Australia. In an interview at HBO’s Santa Monica, Calif., headquarters, Mr. Theroux talked about Kevin’s lustrous beard, and his wife, Jennifer Aniston. These are edited excerpts from the conversation.

Do you ever read a script and think, “Kevin is going to do what?

It’s bananas. Damon definitely likes to put everyone on the end of a prong at a certain point [laughs]. I felt like I got a very unfair share of very uncomfortable scenes in Season 2. There was a lot of water. A lot of times, it was 115 degrees — or almost freezing. So you try and protect yourself. Like, “How many takes are we going to do?”

As in, “I will slither naked out of the bathtub five times, and that’s it.”

That was actually one of the harder ones. The shot they wanted was an overhead of me just lying flat in the tub. I felt like I was drowning.

Why did “The Leftovers” become much more celebrated in Season 2?

What initially attracted him [Mr. Lindelof] to the material was that it was this great portal to talk about things that he’s really interested in: grief, hope, the meaning of life. He was sourcing [Mr. Perrotta’s] book in a good way. Then, in the second season, he was like, “O.K., now I can really charge hard at the questions I want to ask.” It’s kind of like if you want to enjoy a hot cup of soup by the fire, you have to walk through the blizzard to get it.

Do you agree that Kevin takes off his shirt a lot?

There’s always a reason for me to be shirtless. I’m either being rebirthed into a different astral plane — it does make a certain amount of sense that he would be naked. Or I’m waking up with my wife in the morning. It’s not “The Dick Van Dyke Show.” I’m not going to be wearing baby blue pajamas.

Explain all those beards in the new season.

[Mr. Lindelof] told me to start growing a beard. Then strangely all the other guys showed up with beards, too, unasked for. They said, “Do you want us to shave?” And they said: “You know what? Keep your beards. Let’s see if that works.” I think Damon wanted to show that Kevin had settled into the town, become more of a part of the community.

Do you keep your wife up to date on all the scary things that are happening to Kevin?

I do. But knowing about it and being there while it’s happening is a totally different thing. There are times when she’ll call me, and she’ll be out with friends, and I’ll be at the bottom of a well with mud all over me. And I’ll be like, “I really have to call you back.” [laughs]

Talk about suddenly becoming the subject of screaming tabloid headlines.

It’s sort of like there’s this avatar that’s been born who has nothing to do with me or my day-to-day life whatsoever. I once had someone smart tell me, “Look, you’re going to have to get cozy with the fact that there’s a crazy person out there who lives on the covers of the tabloids. This person has no relationship with who you actually are — even though he has your name and face.” [laughs]

Your next film is “The Lego Ninjago Movie.” What’s it about?

It’s about six ninjas, and then there’s an evil warlord named Garmadon. I’m the evil warlord. The minute I tell any of my friends, they go [trembly voice] “Oh my god, so-and-so is going to freak out.” They’re usually talking about a 7-year-old. It’s sort of like an incredibly successful TV show in the world of Lego that is almost like “Fight Club.” You have to be under 10 years old to know it exists.