Florence Pugh and Molly Shannon one-on-one: Inside their mother-daughter relationship in A Good Person

Allison seemingly has everything going for her — professional success and ambition, an amazing fiancé. But then, a split-second moment in time changes everything in catastrophic ways. A year later, still wrapped up in crippling guilt, fear, and physical pain, she is struggling to move on. Her mom Diana is both aggressively concerned and supportive... to an enabling fault.

Oscar nominee Florence Pugh and Emmy nominee Molly Shannon bring the two to life in A Good Person, the latest movie from writer-director Zach Braff. While, on the one hand, the story focuses on Allison's battle with her addiction to pain pills, it also centers on more existential matters of forgiveness (both of others and one's own self), remorse, worthiness, and redemption — especially once Allison comes face to face with Daniel (Morgan Freeman), whose own life she changed on that fateful day.

Pugh and Shannon sat down for a one-on-one EW interview, where they gave intimate insight into the mother-daughter relationship. Below, read excerpts from that interview (the full video of which you can see above) as they talk about their emotional struggles that turned physical. Watch the video above to hear about their favorite scenes and how they both approach scene preparation — including why Shannon uses her pool to help memorize lines.

MOLLY SHANNON: I've done scenes that are physical with other people where they want it very mapped out, like, "You grab me here, then I'll fake-slap you" — I love how real you are. I feel like we both were the same with how we [approached our fight over the pills]... that we both wanted to go for it and that it felt so unhinged and wild. How did you feel during that scene? What was your experience?

FLORENCE PUGH: I loved that we were the same. I loved that every time I ran up those stairs, I was genuinely scared that you were going to come and get me. It fully felt like I had said some s--- to my mom, and my mom was now going to come and get me, and I was in trouble. When I started running up those steps — I still feel it now — my toes would get adrenaline, like I would actually feel my toes go. And my stomach would flip, like, "Oh s---, I've gotta [run]."

The reason it looks terrifying is because we were both so emotional and so physical, and the desperation to prevent me from getting those pills was heartbreaking. And so aggressive. We were both aggressive. It was amazing.

SHANNON: I remember, like, "Florence is tough!" You're like a little tank. I remember the mirror crashing, and that was wild. It was almost like the kind of thing where you don't feel anything while you're doing it, and then you're like, "Ow." But it felt so good.

PUGH: Between The White Lotus, The Other Two, and this movie, you've been playing very different mothers recently — what were you particularly excited to explore with Diane?

SHANNON: [Allison and Diane] have a very close relationship because she's a divorced mother — they're almost like friends. When there aren't two parents, it can become very like sisters almost. I really liked their relationship. I think you could really sympathize with Diane's position. She loves [Allison] so much, and she almost feels powerless; she doesn't know what to do. She's trying to get you off the pills, she's worried, she enables... She tries tough love, and then she's like, that's not working. So she gets to the point where she's like, "Okay, here's the pills. Just, honey, please..." And you can really understand if you were dealing with a loved one and substance abuse, there is no easy answer. There is sometimes ambivalence in wanting to quit; there are obviously good things [Allison] gets from using — she just wants to numb out, and she doesn't want to feel the pain. So you feel the dynamic between the two makes sense — it's very understandable.

PUGH: They've had to be there for each other for a long time, and I had a few girlfriends growing up who had similar situations — only had their mom, or they knew their dad, but their dad didn't live nearby — and only grew up with mainly their mother as their parent figure. It was very similar, the hot and cold nature of the relationship because they only have each other and they can't bear to lose each other. Then the idea of you accidentally then giving the pills back, you don't want to lose that one person that you have... It's almost like you are each other's couple. You are living together.

A Good Person is in theaters now.

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