Annaleigh Ashford Says She's 'Continually Shocked' by Happy Face Killer's Daughter's 'Strength' (Exclusive)

Working on Happy Face brought up a lot of emotions for Annaleigh Ashford, who portrays Happy Killer Keith Jesperson’s daughter Melissa G. Moore.

“I'm really grateful to share her story,” Ashford, 39, tells PEOPLE. “I feel really honored. She's taken this moment of trauma and turned it into something good, which feels impossible.”

Ashford had the opportunity to speak to Moore as she prepared for the role. “She was incredibly helpful in helping us not only understand her life, but also her relationship with her father,” the actress says. “What surprises me the most is how open Melissa continues to be about this tragedy that is her family history because she knows how helpful it can be to people. I'm continually shocked by her strength.”

The Broadway star describes Moore as “so well-adjusted” and “so kind and considerate and caring of the victims” involved in her father’s case. Ashford believes Moore “has navigated this outrageously beautifully. “

“She's been so generous with us in both her experience, her knowledge of victims, her knowledge of taking care of the victims, knowing that every time she tells her story, it's an opportunity for people to anybody involved to rehash,” Ashford continues. “She has navigated this outrageously beautifully.” 

Happy Face follows Melissa as she decides to tell her story to the world in hopes of identifying a ninth victim killed by her dad. 

“She was offering up such a selfless act to come forward and out herself as the daughter of this man,” Ashford says. “It's a really brave and bold act of self-love to acknowledge the shame that you can carry for a crime that you didn't commit. And it's a reminder that even if your family, if somebody didn't commit a crime, you carry around your family's shame.”

Ashford believes Happy Face demonstrates “ancestral trauma.” 

“People carry what their relatives did in generations past,” she says. “And I think it's an act of self-love to admit it and to acknowledge it and to release yourself the burden of the shame that you carry of other people's behavior.” 

Dennis Quaid plays Jesperson — who was sentenced to a life in prison without parole — and Ashford calls it “a treat” to star opposite “one of our greatest all time actors.” 

“He has so much vulnerability and heart,” Ashford says of Quaid, 70. “ You see not only the character's mental health issues and also his love for his daughter. That's ultimately the part of their story that's so complicated.” 

Ashford describes Happy Face as “really beautiful,” which she acknowledges may be an unconventional way to refer to a true crime series. 

“It's beautifully shot, it's beautifully written,” she says. “To say beautiful so many times about a topic that's so horrific, I think we're really coming at true crime from such a different space and place, from the conversation of family and giving the ownership back to the victims and away from the perpetrator. We're not telling his story, we're telling Melissa’s story, and I think it was really important for Melissa. It gives us the power, and it gives the victims back their power.”

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Happy Face premieres Thursday, March 20, on Paramount+.