Angelina Jolie was grateful for an audience full of understanding extras when it came time for her to sing on stage Mary.

The Oscar winner, 49, portrays the famous opera singer Maria Callas in the new film, mixing real-life singing with some of the actress’ own voices. But even in performance sequences, most of which were Callas shots, Jolie had to belt out “loudly” to sell the scenes.

“The funny thing is that when you sing opera you have to be very loud to be convincing, as loud as you can. Whether you feel safe or not, you still have to be very loud,” Jolie said in an interview with Netflix’s Queue.

Director Pablo Larraín, she explained, “did a wonderful thing by casting a group (of extras) who remained in the audience (throughout filming).”

“They accompanied me to a few performances, and these wonderful people became so important to the play,” Jolie said, adding, “I think the first day I met them I said, ‘I apologize for that, what would happen if that happened.’ I made the wrong notes out loud.’ ”

Jolie said: “It helped me that I was performing in front of a real audience. They were really nice people who knew I was doing my best, and I wasn’t an opera singer, but I was learning. We were connected by this. “Their understanding and support were everything.”

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The actress previously said she underwent vocal training for seven months to prepare for her role.

Jolie told diversity in October that singing lessons turned out to be “the best therapy I’ve ever had.” She added: “Honestly, I think I would tell a lot of people before they try therapy and spend too much time there, go to singing lessons.”

“It helped me a lot,” she said. “There’s something primal about finding your voice in your own body.” It brings up certain emotions that you might not have wanted to deal with, and there’s no way to sing in full voice and with full emotion without facing your feelings and to set boundaries.”

Mary is now on Netflix.