Billie Eilish autographs Melissa McCarthy’s head at SAG Awards 2024

Wait — did that just happen?

Talk about a real headline.

Billie Eilish took a magic marker and “autographed” Melissa McCarthy’s forehead live during the 2024 SAG Awards Saturday night when the duo were presenting the award for Female Actor in a Comedy Series.

(“The Bear” star Ayo Edibiri won the award.)

The bit started when Eilish, 22, pretended that she never met McCarthy, 53, before they appeared onstage — and McCarthy reminded her that, yes, they had met several times before.

“We met twice … actually we met thrice,” a flustered-looking McCarthy said. “You met my daughters and my dog.”

As Eilish looked on bemused, McCarthy then told the “Ocean Eyes” singer that she actually met her “in utero,” since Eilish’s mother, actress/producer Maggie May Baird, was McCarthy’s first improv teacher.

McCarthy continued. “I’m just trying to be more present in making memories — trying for more YOLO-ing and less FOMO-ing,” she said, as the audience roared with laughter. “Would you mind signing my dress?”

“I don’t want to ruin it,” Eilish replied.

“Thank you for liking my choices,” McCarthy responded.

And then came the shocker: “Will you sign my face?”

“Oh, yeah, for sure,” Eilish said.

“I thought you’d be like, ‘I don’t wanna ruin your pretty face,’” McCarthy said, looking faux surprised.

“I don’t care,” Eilish said.

She then took out a felt-tipped pen and started to sign her name on McCarthy’s forehead — and when McCarthy asked Eilish about her and her older brother and producer, Phineas, “putting down sick tracks,” Eilish put her hand over McCarthy’s mouth. She then began inking her name on McCarthy’s forehead — while McCarthy gave her a thumbs-up.

Eilish tried to hold in her laughter, and ultimately managed to finish signing her name.

“Oh, that was unexpected!” McCarthy said, holding the marker when Eilish finished — and then sniffing it before putting it away.

The bit kept the audience in stitches throughout — as the camera cut to “The Crown” star Elizabeth Debicki laughing uncontrollably and covering her face.

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