Emmy Award-winner Jean Smart has embodied some memorable television characters over the past three and a half decades, from office manager Charlene Frazier-Stillfield (“Designing Women”) and former high school flame Lana Gardner (“Frasier”), to first lady Martha Logan (“24”) and family matriarch Floyd Gerhardt (“Fargo”). Her latest small-screen role is sure to follow in those footsteps: In HBO’s “Watchmen,” she plays the formidable FBI agent Laurie Blake, who happens to have a mysterious superhero past.

How did you most connect with Laurie when initially reading the “Watchmen” script?

When I first read the script I just loved it and loved the role and when I spoke to Damon [Lindelof, the creator] I was worried he was going to say that he didn’t want her to be all that funny but I found her very funny and was hoping he agreed. And he did; he said, “She’s got to be funny.” So I was relieved that we were on the same page about that. I suppose I have a similar sense of humor to Laurie. I’ve always, even as a kid, used humor to sort of deflect from uncomfortable situations and things, so it was something that I felt fairly comfortable with.

When the audience first meets Laurie, she seems very in control of her surroundings; is this who she truly is?

I think she’s a very guarded person. I think that’s just who she is from her background and things like that. She lives alone and all she has in her closet are black suits and she’s kind of a lonesome character. But she feels, I think, that she’s in complete control and wants people to think she has everything all figured out — which is partly why she’s such a smart-ass. Of course, when we see her in the phone booth talking to John is when we see more of the real her, which doesn’t come out very often.

How much of her journey this season is to figure out others’ secrets, versus to have others figure out her own secrets?

I don’t think she ever thinks that people can figure her out; I think she thinks she covers herself really, really well. But she certainly sees with Agent Petey — she’s kind of writing him off as a geeky fan and comes to realize there’s a lot more to him than at first glance and comes to sort of respect and, dare I say, be fond of him. That was a real fun relationship to play with because boy is she hard on him, but the more he is able to take it and not quit, the more she likes it and the more crap she gives him.

Have you shot flashbacks to reveal some of Laurie’s secrets and backstory?

No, I haven’t. It may be something Damon wants to get into later, but at the moment it’s just interesting backstory for me because she was obviously somewhat damaged by her upbringing and does not have much respect for her parents — which is a sad thing, ultimately. It’s a very lonely feeling and she’s a very lonely person. But because there was so much there on the page — particularly that first episode where she is introduced is so complete and so clear to me the kind of person she was that at that point I didn’t feel a lack of research or anything was a problem. That episode was just a gift in a gift box; it was just so much fun and three-dimensional. The fact that I knew Adrian Vieidt before, that I had known Senator Keene before, all of those relationships it was important to have some kind of backstory. The only issue I had at all was in that first episode my knee was in a brace because when they had offered me the part, 48 hours beforehand I had had a procedure on my knee. So I was like, “Oh no, you want me to play a badass FBI agent!?”

How do the relationships she begins to form, with Agent Petey (Dustin Ingram), as you mentioned, or with Angela (Regina King) shape her arc?

At first Angela is a murder suspect, but I think Laurie figures out pretty quickly that that’s probably not the case. But she does know that Angela’s hiding a lot and there is a lot more to the story than she first thought. I think she first thought she was going to breeze into Tulsa, solve this crime and go home to her owl. But she found that there were all sorts of things that she had no idea. When she tries to intimidate Angela, boy does that backfire! I think there is a grudging respect there, and at their heart, they are both law enforcement. I think they both think they’re doing the right thing. At first they are complete adversaries but I think they come to not quite a friendship but something where you could see they could someday work on the same side.

How much of the alternate world setting was a draw in general for you?

That was real interesting because I wasn’t real clear about that. There’s no plastic and there’s different tech; where the heck are we? But there’s a timelessness to the show that I think is fun and also advantageous for us if it goes on into the future. Certainly it being in some ways a fantasy show they can go a lot further with the bad things, with the scary things, but we also want it very much rooted in reality, and it is interesting how much was written in that book in the 1980s resonates today. Especially the whole theme of fear — people being fearful of their fellow man, people being fearful of their fellow citizens, people using fear to control us — it’s so prevalent today.