Melissa Joan Hart Has a Breakdown in Dramatic New Lifetime Movie: Here's a First Look (Exclusive)

'Dirty Little Secret' premieres Saturday. The actress talks to ET about playing a hoarder.

Melissa Joan Hart is at her breaking point in a dramatic new Lifetime movie.

Inspired by real-life events, Dirty Little Secret -- part of the network's "Ripped From the Headlines" slate -- follows 17-year-old Lucy (Lizzie Boys) who has been painfully isolated from her peers for years, refusing to let anyone near her house in order to hide her family secret: the overwhelming mountain of items filled in every crevice of space in her home. She quietly plans her escape to college while managing her mother Joanna’s (Hart) hoarding disorder. Outwardly, a highly functioning nurse, Joanna maintains the dysfunction in their home with an obsessive grip but after a tragedy, Lucy must decide if she will hide her mother's secret, or expose it to the world.

ET exclusively premieres a first look at the upcoming film, which finds Lucy carefully tiptoeing around her mother, who begins their conversation innocently enough amidst piles and piles of stuff. See, Joanna has a dream of one day living in a pristine home without all the clutter and mess she's surrounded by on a daily basis, as she shares the idyllic future with her daughter.

"I always told you, honey, it's messy right now but it's just temporary," Joanna assures Lucy, who's not buying into anything she's saying. When Joanna continues to talk about finding the chair they're looking for that would make their nonexistent future home perfect, things take a turn for the worse when she asks Lucy to give her a pair of scissors.

When Lucy shares that she's not sure where they are, Joanna -- who claims her daughter was the last one with them -- loses her temper when her memory fails to line up with reality.

Confronted with that revelation, what was a pleasant conversation between mother and daughter quickly turns sour as Joanna has a huge breakdown. 

"Lucy, you always borrow my stuff and you never put it back where it belongs!" she screams. "And then you shift the blame to me! I work 12 hours a day and then I come home to take care of you and nothing is where I left it!" 

Looks like things are about to get worse. Watch the exclusive clip below.

Hart stopped by ET's New York office on Thursday to promote the upcoming movie and explain why she was drawn to her character and the story as a whole.

"My character, Joanna, in Dirty Little Secret, she's the epitome of hoarding behaviors," the actress told ET. "She is a hoarder. She's a nurse during the day and she's a hoarder at home. She's living with her teenage daughter and you find out that she has two other children who are grown and left the house because they couldn't handle the mess. But we really incorporate in Joanna -- I worked with a psychologist, I worked with acting coaches and movement specialists to really bring this woman alive and really tell the story properly."

"I really thought this was an important story to tell but it's a departure from my usual comedy and whatnot. But it's also a true Lifetime, from the headlines, juicy, juicy movie," Hart continued. "My character, Joanna, pretty much embodies every hoarding thing you can think of. She's suffered loss, she was OCD and it flipped to hoarding behavior. She puts monetary value on things as well as sentimental things -- all the typical things you would see in hoarding behavior."

Hart expressed the importance for her to "do the [story] justice, acknowledging that she didn't know the complexities of hoarding behaviors beforehand. 

"The more I learned, the more I realized we're all one step, one degree away from this because I’m a collector. If I go out, if I travel, I bring back a sugar packet, a shot glass. I bring back a piece of ceramic, but if I didn't have enough shelf space would I be a hoarder?" she asked. "I put a lot of sentimental value on things. I remember how much they cost and they do say that a lot of people that become hoarders are people that grew up with not much and so they want to hold on to everything."

"What I put into Joanna -- the sort of mantra going on in my mind was 'not today.' A lot of the time with hoarding behavior it's 'not today,' like today I’ll make the drapes, I want to have a dinner party, I’ll clean up that room but not today. It's always putting things off, feeling like I’m too overwhelmed, I’m too busy," Hart noted. "If you look at the set we were on, it's overwhelming. It was gross. I wanted to clean it up so badly, it was killing me."

She also spent a lot of time focusing on her physical appearance to get into Joanna's mindset. "This is probably one of the first times I had to focus on my appearance in a different way. Usually you want to be as pretty as possible. Should I get the Botox? Should I dye my hair a little blonder? But for Joanna, because she’s a hoarder but also a nurse, she has to appear a certain way and be clean enough to do that job well and then be able to go home. So I dyed my hair a natural dirty blonde so it didn’t look done but it didn’t look undone. My nails, we just kept filed, no paint. Kept them simple. We have a scene where my daughter is filing my nails, which helped explain that self-maintenance and how you can hide it for so long."

For Hart, who also hosts her own podcast, What Women Binge, the personal possession she owns that she'd hang onto and that has the most sentimental meaning would be her grandmother's music box. "[It] is the song I walked down the aisle to at my wedding and that was very special to me," she shared, adding she'd also take an original Picasso painting she owns. And, of course her "wedding ring." 

Dirty Little Secret premieres Saturday, June 11 at 8 p.m. ET/PT on Lifetime.

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