After scoring big with Netflix’s “The Kissing Booth” last year, actress Joey King returns as Gypsy Rose Blanchard in Hulu’s anthology series “The Act.”

The stranger-than-fiction series centers around Blanchard and her mother Dee Dee (Patricia Arquette), who suffered from Munchausen syndrome by proxy, a condition where a caregiver either fabricates or induces an illness in someone under their care to gain attention and sympathy.

“It was such a mentally challenging role for me,” King told TheWrap. “It required a lot of vulnerability.”

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For years, Dee Dee had convinced everyone — including Gypsy — that her daughter had leukemia, asthma, muscular dystrophy, and the mental capacity of a 6 year-old, as a result of her premature birth.

All the while, Dee Dee collected donations from non-profit organizations, including the Make-A-Wish Foundation.

But none of it was true. In 2015, Dee Dee was found dead in her bed, after being stabbed several time in her sleep. Gypsy and her online boyfriend, Nicholas Godejohn were later convicted of the crime.

The story of Gypsy and Dee Dee was first told by the show’s co-creator and co-showrunner Michelle Dean in a 2016 BuzzFeed feature. It was later turned into an HBO documentary “Mommy Dead and Dearest” in 2017.

“I feel really sorry for her,” King said about Gypsy. “Here is a girl who had no idea how to get out of a horrendous situation she was trapped in and so she took extreme measures.”

Gypsy is currently serving a 10-year prison sentence at the Chillicothe Correctional Center in Missouri. Godejohn is serving life.

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“She did something horrible,” King said. “But it’s such a complex, complicated story with so many layers, I think it’s so unfair to pin her as a cold-blooded killer.”

“She was a victim for 23 years of her life or more. I can’t imagine what that must have been like,” she added.

Watch the interview with King above.