How Dirty John: The Betty Broderick Story creator crafted a marriage horror story

After a grueling shoot day in the upcoming season of Dirty John: The Betty Broderick Story, star Amanda Peet, who plays the titular Betty, a SoCal socialite who is left without her children and husband after an ugly divorce, goes home to her kids. She can't believe what she's been through. She can't believe what her character has been through. She looks at a mirror.

"I came home with this '80s makeup. I had been working for 13 hours," Peet recalls. "I look in the mirror. I look like a middle-aged Joker. I was like 'Wow, I might be losing it.'"

Back in season 1 (commissioned by and broadcast on Bravo), Dirty John creator Alexandra Cunningham had the hype of a popular podcast to boost her show's viewership: a cautionary true story about another Southern California woman conned into a disastrous marriage. The show was a hit, earning Connie Britton an Emmy nomination for her performance as Debra Newell. In season 2, which has moved to Bravo's sister network USA, the proverbial book was closed on Debra and John Meehan. But Cunningham & Co. had an idea: They'd make the series about "love gone wrong," and their next subject fit the bill to a frightening T. In 1989, Betty Broderick killed her ex-husband and his second wife, and soon after was sentenced to 32-years-to-life in prison.

"We can all relate to wanting to be loved, wanting to trust, and wanting not to believe that the person that you love and trust could be your worst enemy," Cunningham tells EW.

Based on the book Until the Twelfth of Never, by Bella Stumbo, The Betty Broderick Story pits Betty against her husband, Dan (played by Christian Slater), a malpractice attorney who gaslights his wife into believing he's not cheating with Linda (Rachel Keller), a receptionist at his firm. Betty and Dan, who married in 1969 with little to no money to their name, had everything they could ever want in the '80s: Money. Power. Status. But as soon as they could begin rejoicing, their bridge of love and comfort burned to a crisp.

"She's not going to be the last angry person who didn't get as much love as she needed," Cunningham says of choosing Broderick as her next subject. "Who embarrassed her friends and made them avoid her because she was so angry and she couldn't let things go. She's not going to be the last person who shoots and kills people because she feels like she doesn't have an identity anymore."

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To be clear, this isn't a Betty Broderick revisionist story, Cunningham says. In fact, Cunningham is taking on a larger white whale that may have ultimately broken Betty, the real nightmare: divorce.

In the first episode, "No Fault," alluding to the no-fault divorce policy, Betty says, "Divorce is the closest most people come to war." And that's exactly what the eight episodes of The Betty Broderick Story are: an all-out blitz from both sides, including a car crash that leaves Betty in a straitjacket in the premiere.

This is Betty coming apart at the seams, but how much of it is due to Dan, and how much of it is due to their intense legal battle?

"No-fault divorce was meant to sort of equalize things in the courtroom between the sexes," Cunningham says. "That was supposed to be a good thing. That knee-jerk concept that we're all kind of aware of is the 50-50 split [of property]. I have yet to see that pan out for anybody."

She adds, "It is not my intention to have created a thing that bashes Dan. Dan created a bear that he couldn't stop poking. It was cyclical until the bear went rogue."

Peet viewed her character through the lens of mental illness. During Broderick's trial, a psychiatrist testified that she "suffered from dual-personality disorders and that her behavior was characterized by wild exaggeration, petty vindictiveness, and homicidal rage," according to a Los Angeles Times article.

"We weren't interested in doing an imitation of her real life," Peet says. "What Alexandra was really passionate about was the psychological torture and how she showed signs earlier in her life that this could have happened."

Broderick's simmering homicidal rage may or may not have not been in part due to her husband and/or the divorce, but at the end of the day, Peet says, you're not supposed to take sides either way.

"The bottom line is, she's a murderer," she says. "She did it, and there are no two ways about that. Part of my job was to try to relinquish all judgment as soon as possible and try to understand where she was coming from."

Season 2 of Dirty John debuts Tuesday, June 2, at 9 p.m. ET on USA.

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