Mia Tomlinson recalls her young Lorraine audition and why she kept her sights set on playing Judy Warren.Director Michael Chaves admits he was “a little frustrated” when he no longer had his young Lorraine but says, “There is no better Judy that we ever saw.” Tomlinson explains how she created two versions of Judy to play in the film: Judy and evil Judy.

This article contains spoilers from The Conjuring: Last Rites.

Mia Tomlinson made a rather bold choice to land her biggest role to date, that of adult Judy Warren in this weekend’s event horror film The Conjuring: Last Rites.

The British performer, seen in Britbox thriller The Beast Must Die and Netflix’s dramatized docuseries The Lost Pirate Kingdom, auditioned first for Judy before casting asked her to read for young Lorraine. The opening sequence of the film flashes back to meet demonologists Ed and Lorraine Warren, played across the franchise by Patrick Wilson and Vera Farmiga, while on their very first case as paranormal investigators. Tomlinson auditioned with material for this sequence, which involves Lorraine going into labor and suffering a stillbirth.

“I actually don’t have so much memory from doing that audition because it was so emotionally taxing,” Tomlinson tells Entertainment Weekly. “When I came to, I was like, ‘Oh, Mia, have you overdone this?’ There’s a bit much screaming and crying, and there’s this baby, and it’s dead. It is awful. It was so awful. And then I realized that they were all teary and in shock from it and had, obviously, experienced it with me, which was amazing.”

Director Michael Chaves recalls his reaction to her delivery. “I’m floored,” Chaves says. “She does an incredible young Lorraine. It’s the emotion. Tears are blowing up in my eyes.”

Tomlinson, he says, would be young Lorraine. She, however, kept her sights on Judy.

Evil Judy (Mia Tomlinson) in ‘The Conjuring: Last Rites’.

Courtesy of Warner Bros. Pictures

The Conjuring: Last Rights marks the first time audiences meet Judy in her adult years, after previously seeing her child and teenage years through performances from Sterling Jerins and Mckenna Grace. The movie is, in many ways, about Judy and the psychic abilities she got from her mother.

“Judy was just the more intriguing character for me in terms of where I was at as an actor,” Tomlinson explains. “I’m quite an expressive and bubbly person, so it’s really interesting for me to play somebody that’s got to keep that all inside and force it to come out. We obviously see those [joyful] moments in the film, but through the majority of it, it was really about wearing a mask the whole time and hiding everything.”

One scene in particular captured her attention. Judy eagerly tries on wedding dresses at a local shop in a room walled off by mirrors. When her mother leaves the room for a moment, she’s accosted by a demonic entity that toys with her through funhouse-style reflections, creating this evil doppelganger of Judy.

“What that reflection is showing is a young woman in a wedding dress who’s feeling good initially, which is exactly how she wants to feel,” Tomlinson comments of that sequence, “and at the same time, [showing] something terrifying, something ominous about herself, because what’s in the reflection is the dark versions of herself. When I read that in the script, I was like, ‘Please don’t find another Judy! Please keep me here. I wanna do this.'”

So she made a decision. Chaves asked her to come back the following week and read again for both Judy and young Lorraine. “I was like, ‘I’d come back, but for Judy,'” Tomlinson reveals. “I’ve never done that. I’m British! That’s also a very big point to say here, because British people, we’re normally a bit more like, ‘Oh, thank you so much. So, so sorry for being here.’ I left the room and I called my agent. I went, ‘I don’t know why I did that?! I just want a job.'”

Vera Farmiga and Mia Tomlinson in ‘The Conjuring: Last Rites’.

Giles Keyte/Warner Bros

Chaves admits he was “a little frustrated,” but felt confident he could convince Tomlinson later on to play Lorraine. The studio brought in several “high-profile actresses in their 20s” to read for Judy, the filmmaker says. However, “We go through the day, all these high-profile actors come in. No one matches Mia. No one touches that performance,” he notes. “There is no better Judy that we ever saw.”

After an extended search between the U.K., the E.U., and the U.S., Chaves finally found his younger Lorraine in Madison Lawlor — and Tomlinson, finally, got the Judy job. Afterwards, Tomlinson created two versions of the character in her head to bring to the table: Judy and evil Judy. The character is often taunted by her devilish reflection, and then a sequence in the climactic finale sees the Warrens’ daughter become fully possessed by the demonic entity.

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For inspiration, Tomlinson looked back to her childhood, when she would regularly tease her younger brother and sister by jumping out from behind corners and scaring them. After watching The Conjuring: Last Rites with Tomlinson in London, her brother remarked, “I recognize a few of those faces.”

“We had this long corridor in our flat in London as kids. I used to hide out in the corner in the doorway of one of those rooms so that when they walk past, they jump out of their skin,” Tomlinson says, cackling with that same evil Judy smile. “So I was ready for evil Judy Warren. I actually, probably, wanted to make her more evil.”

In the end, Tomlinson’s risk paid off, though she recognizes it’s likely because Chaves found her advocacy for the role charming rather than off-putting. It’s not the kind of bold statement Tomlinson usually made as an upcoming actress. “Moving forward,” she adds, “I don’t know if I would take it again!”

The Conjuring: Last Rites is playing now in theaters.