Joaquin Phoenix Scared Joker: Folie à Deux Costar’s Mom By Appearing on Their FaceTime in Full Joker Makeup

It seems that Joaquin Phoenix lived up to his Joker: Folie à Deux character’s name on set.

While speaking with Variety about the upcoming comic book movie sequel, actor Harry Lawtey said that Phoenix, 49, “suggested, as a joke, that we FaceTime my mum and scare her” during a rehearsal — while the Academy Award winner remained in full clown makeup for the role.

“My mum was in England, so it was quite late, and she was getting ready for bed. And I said, ‘Hello,’ and then I brought the phone up to my face, and Joaquin put his head on my shoulder,” Lawtey, 27, recalled. “My mum screamed, ran away and woke up my dad.”

Lawtey, known for his role on HBO’s Industry, is playing Harvey Dent in the upcoming film, which also costars Lady Gaga, Brendan Gleeson, Catherine Keener and Zazie Beetz. The highly-anticipated movie releases exactly five years after filmmaker Todd Phillips’ 2019 movie Joker, which received 11 Oscar nominations and won two, including Phoenix’s Best Actor win.

The new movie “finds Arthur Fleck institutionalized at Arkham awaiting trial for his crimes as Joker,” according to an official synopsis for the film. “While struggling with his dual identity, Arthur not only stumbles upon true love, but also finds the music that’s always been inside him.”

Lawtey additionally told the outlet that Phoenix’s performance in the film amounted to “a master class” on set each day.

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“To watch him do that laugh and to see the effect on him — on everyone — blew my mind,” he added of Phoenix’s commitment to the role. “He would be coughing after each take. It was an education to watch him move through different flavors and shades of that performance.”

Lawtey’s take on Harvey Dent — the character that has memorably been played by Aaron Eckhart, Billy Dee Williams and Tommy Lee Jones in live-action Batman movies over the years — appears to involve courtroom showdowns with Phoenix’s Arthur Fleck, as he told Variety. Even so, Lawtey does not sing in the quasi-musical sequel.

“I mean not singing in front of Lady Gaga is something that I am OK with,” he told the outlet. “If there’s someone in that room who should be singing, it’s her. And getting a front-row seat for that, it was a goose-bumps moment.”

Joker: Folie à Deux is in theaters Oct. 4.