Joker: Folie á Deux casting director Francine Maisler has recently praised Lady Gaga as Harley Quinn in the upcoming movie.

“She’s so good in it, you guys. She’s going to blow your mind,” said Maisler while speaking at the Karlovy Vary International Film Festival, via Variety.

Maisler revealed that Gaga as Harley Quinn opposite Joaquin Phoenix was not originally her idea. It was director Todd Phillips who selected the pop star.

“I didn’t suggest Lady Gaga. It wasn’t my idea. That was Todd Phillips, before me. But I will tell you, she’s really surprising — and really good,” admitted the casting director.

Maisler further said, “I saw it and I was really surprised. I mean, we all knew what she could do in ‘A Star Is Born,’ but I thought, ‘Oh, well, that’s kind of in her wheelhouse.’”

“Something she could do and just be real. But this… Man, she’s good,” she remarked.

Maisler added, “Joaquin blows your mind, but that she could keep up with him, and be real — and not just wiped off the screen by what that role is and what the performance is — shows she’s good.”

Earlier in an interview with Access Hollywood, Gaga shared her thoughts on Harley in the movie.

“The character is very authentic to this movie and these characters,” clarifying that fans should not expect similarities to what Margot Robbie did in bringing Harley to life in films such as Suicide Squad and Birds of Prey.

Robbie also gushed over Gaga in a Variety cover story last year.

“Harley’s so fun and can go in so many different directions. You put her in someone else’s hands, and it’s like, ‘What are they going to do with her?’ The options are endless,” stated the Barbie star.

Meanwhile, Joker: Folie à Deux will release in theatres on October 4.