The 45-year-old wowed in a glittering Oscar de la Renta gown at this year's Golden Globe Awards, where she was nominated for Best Actress in a Limited Series or Motion Picture Made for Television for her role in "George & Tammy."
The embellished gown had a sheer mesh underlayer and heavy beaded detailing, and came with a matching face mask that Twitter users couldn't get enough of.
"We love to see [Jessica Chastain] mask up in style for the 2023 Golden Globes," one person wrote.
"Best mask clearly goes to Jessica Chastain… who said COVID-19 protocols can’t be fashionable?" another shared.
"I’m sorry but Jessica Chastain getting a matching mask for her dress is adorable," wrote a third.
"Jessica Chastain always understands the assignment when it comes to red carpet [fashion]," one Twitter user penned.
Earlier in the day, Chastain's stylist Elizabeth Stewart showcased the spiderweb-inspired dress, plus the stunning accessories that went along with it.
"Jessica Chastain heading to the Golden Globes in Oscar de la Renta!" Stewart wrote. "Please swipe to the last slide to see the real star of tonight, Orsolina Garcia, who expertly tailored this dress after our last minute noon fitting! Rings by Gucci and shoes by [Casadei]."
In the first photo of the Instagram carousel, Stewart shared a photo of Chastain looking off to the side as her glam squad stands by in the background. In the second, she looks straight into the camera while wearing the beaded face mask to match the stunning red carpet gown.
In the other three photos in the carousel, Chastain poses with Garcia, who finished the gown's alterations "in the nick of time" ahead of the awards show.