Dennis Quaid Was 'Not Really Interested' in Playing Happy Face Killer Keith Jesperson: 'He Disgusts Me' (Exclusive)

Dennis Quaid initially wanted to say “no” to playing serial killer Keith Jesperson in Happy Face.

“He disgusts me, to tell you the truth,” Quaid, 70, tells PEOPLE of Jesperson. “I'm not really interested in playing a serial killer, but it was the relationship with his daughter — and the story is told from her point of view — that's the reason I said ‘yes’ to this. That's what made it interesting. It's dedicated to the victims.”

Annaleigh Ashford portrays the Happy Face Killer’s daughter Melissa G. Moore in the Paramount+ series, and Quaid says Ashford, 39, “made my job so much easier.”

“All I had to do was sit there and react to her,” the father of three adds.

In Happy Face, Melissa decides to publicly identify as the daughter of the Happy Face Killer — who was sentenced to life in prison without parole after killing at least eight women — in hopes of identifying a potential ninth victim murdered by her dad. Jesperson, 69, had pleaded guilty to the ninth victim’s murder in January 2010, more than three decades after he killed her in 1992. The woman was ultimately identified in January 2024.

“This is Melissa's story, and I think she knows him better than he knows himself, in ways, because he is a shallow person,” Quaid says. “These guys, they do these heinous acts and certainly there's the victim, but then there's the victim's families and friends who this reverberates out with. She had a very loving, sweet relationship with her dad growing up as a child. And then, at 15, he was caught. How do you reconcile this loving dad with this monster? And what does that do to you as a person?”

Jesperson, 69, earned his nickname thanks to the signature smiley faces he would leave on his correspondences. The Canada-born long-haul trucker turned himself in after killing multiple women between 1990 and 1995 and pleaded guilty to murder charges in October 1995. He is currently serving four life sentences at the Oregon State Penitentiary.

Quaid actually found Jesperson “remarkably easy to play because I don't think he really has emotions,” the Emmy-nominated actor says. “I think he may manufacture emotions, but I don't think he really has them. I don't think he takes responsibility for what he did. There has to be this distance in order for him to be able to live with himself. He just wants to act like he's a regular dad still, and [that’s] not going to happen.”

While Quaid says he understands where Jesperson “is coming from,” that doesn’t mean he sympathizes with the murderer.

“I think what he did was over sex,” the Parent Trap star hypothesizes. “Sex is a very powerful force in us, and he got very twisted somewhere along the way. I don't think he thinks of himself in a good way when it comes to sex. I mean, he committed these murders to hide his evidence. You could talk about your childhood and the rest of that all you want, but I'm not buying it in the end.”

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