“You end up losing their humanity,” Slater says. “But I think this show and what [showrunner] Alexandra Cunningham wanted to do was delve more deeply into what actually happened here between these two people.”

To portray Dan Broderick, Slater had to rely on the script and his conversations with Cunningham to get a sense of who he was. “You know, certainly power hungry, certainly egotistical, very controlling,” he says. “I think he felt that he’d built up such an impervious wall around himself through success, that it was impenetrable. Obviously, Betty continued to try to break down that wall—until she found the final solution.”

Slater took some time to chat with Fortune about the role, his fellow cast members, and dramatizing the case. What follows is that conversation, edited and condensed for clarity.

Isabella Vosmikova—USA Network

FORTUNE: Did you have the opportunity to interact with anyone who knew Dan or the Brodericks in general?

Slater: No. The family was left alone. It’s tricky. It’s a difficult story to revisit, so my heart and compassion go out to the family. Having to continue to live with something like this is extraordinarily difficult.

But unfortunately, this marriage, this divorce did garner so much attention—I think it’s an example story. It’s an example of two people who were close. Betty supported him through medical school, through law school, did everything she could to take care of the kids, but then he became successful, worked so hard that again another wall was built between the two of them. I think they lost connection with what it was that brought them together in the first place. So much distance had been created, and then sadly she ended up becoming the person that reminded him of a time that he wanted to forget about altogether. He didn’t want to think about any struggle. He wanted to keep up the appearance of a person who had it all together and almost continuing to play a role. There was something so eccentric about this guy and so flamboyant that there is a sense of performance that he’s giving throughout his life. Everything needs to look good on the surface.

The other thing, too, to look at is what it was like at this particular time. I think one of the saddest aspects of this marriage and the destruction that took place is the fact that maybe the egos were too big or the availability to get access to help, or maybe even just the willingness to ask for help, was much more frowned upon than it is today. Obviously, it’s still in our society something that is judged to a certain degree, but particularly when this moment happened and when this story was taking place, it was shunned a lot more.

Dan doesn’t necessarily come across that well in the show. Neither does Betty, but we get to see her in a sympathetic light even as she starts to unravel. Do you feel you still had an opportunity to portray Dan as someone with layers?

That was something that Alexandra and I talked about from the get-go—she wasn’t really interested in a Snidely Whiplash take on the character. I mean this wasn’t a mustache-twirling guy—I think this was a guy who fell prey to what the standards were or what the idea was of what a man was supposed to be: somebody in charge, somebody in control. It’s not like this is an unusual story. To a certain degree, there’s a stereotypical quality to this—you hear about it all the time. People get married and they get divorced, and the man becomes successful and he ends up marrying his secretary. The endings don’t always end up this way, but to a certain degree, there can be different versions of ugly endings, so I think he’s relatable.

It’s funny to talk to men about this story and hear their points of view, then talk to women and hear their points of view, because some of the men I’ve talked to while doing interviews have expressed the opposite opinion. Now, I don’t necessarily agree with that—I wish there’d been more honesty, more openness on his part, and like I said, more help. I don’t think you can really go through anything in this life solely by self-will and self-determination. I think it’s important to seek out information and ask for help.

Isabella Vosmikova—USA Network)

Your characters were at odds with each other, so what was it like working with Amanda on-set?

She is known as pretty much being a classically hilarious person. I never worked with her before, but we’ve crossed paths, and I always found her to be hilarious in the interactions that we’d had prior to this. I had always wanted to work with her—I think she’s extraordinarily talented. And I’m just thrilled that there was a role that she had the opportunity to really sink her teeth into. And she really did take it by the horns and just—she delved as deeply as she possibly could, so I admired her professionalism. But at the same time she was extraordinarily funny, did keep people laughing on-set, but was deeply, deeply committed to her interpretation of who Betty was.

Did you work with Chris Mason, the actor who plays young Dan in the show? I noticed he did a pretty solid job of sounding a lot like you, actually.

[Laughs] Well, yeah. He had the benefit—that I didn’t have—of being around me. I wasn’t able to be around Dan Broderick. Chris is obviously a fantastic and wonderful actor. We didn’t know each other, but he did shadow me quite a bit and he would sit in on voiceover recordings for the show and he would watch takes, and he’d always be sort of off in a corner, really committed and really wanting to, you know, capture my voice, which is hilarious and great. I think he did an amazing job. You know, it’s nice, because it’s very tricky to find a way to make that seamless. But I’m grateful he was able to do that.

You’ve been working on a bunch of TV shows in recent years—obviously there’s Mr. Robot, but you’ve also done voice work on Archer. This show is presented more as an anthology series, so it’s a one-off season for you. How did this compare to other TV roles you’ve done?

Some of the TV projects that I’ve been involved with have obviously gone on for other seasons and it gives you a longer period of time to discover your character, which is an exciting aspect. I liked the tightness of this story. I like anthology series—it’s basically like shooting a movie. You’re there for four months, and you know it’s a finite experience, so you’re telling a story from point A to point B in a much more compact [way than a regular series] but less compact than it would be if it were a movie. So it gives you a feeling of being able to relax a little bit more, even in the intensity of the scenes that you’re working on. You feel a little less pressure, but you still have to obviously keep it moving along.

But each experience is different and typically great and fulfilling. To go back to Amanda, it was very nice to work with her. Because there [were] some violent moments in the show and those types of things that happened. She and I really wanted to make sure that we kept each other as safe as possible, and we always talked about those moments. Those physical moments of pulling her out of the car, wrestling her to the ground, and all those kinds of beats that we had to re-create—my main concern was safety. And that was her main concern as well.

Isabella Vosmikova—USA Network)

Did working on this series color your perception of the case in the end?

A lot of this was very fresh to me. This was not a case that I was privy to. Who knows what I was doing when I was in my [twenties], so I didn’t know a great deal about it. At the end of the day, for me, it’s a heartbreaking story. It’s heartbreaking because Betty was somebody who had an idea of what life was supposed to look like and was desperate to cling to that. That was the message that was instilled in her as a young person, and she was obviously willing to go to lengths—great lengths—to maintain and hold onto it and not have what happened happen. She was an intelligent woman. She was a skilled woman. I think she was also put in a position again as a result of the times, of being the happy wife, of looking good.

So much of it becomes about looking good in front of people, in front of the friends that you have at the time. As far as actually dealing with any reality, not a lot of that was happening, And when you’re not dealing with reality, you tend to live in fantasy and delusion land, and that can drive you crazy.

Dirty John: The Betty Broderick story premieres, with two episodes airing back-to-back, June 2 at 9 p.m. ET on USA.