Millie Bobby Brown knows what is “Good 4 U”.

The “Stranger Things” star shared a video of herself lip syncing and dancing around in the bathroom to Olivia Rodrigo’s newest hit.

“Thank you @Oliviarodrigo you are a legend and i love you. okay bye. thanks again,” Brown captioned the clip on Instagram Stories.

RELATED: Olivia Rodrigo Details Handwritten Letter From Taylor Swift: ‘You Make Your Own Luck’

Millie Bobby Brown Instagram Stories. Photo: @milliebobbybrown/Instagram
Millie Bobby Brown Instagram Stories. Photo: @milliebobbybrown/Instagram

She then shared a DM Rodrigo sent her, reading, “I love you. period.”

“okay. no. that’s it fr now,” Brown joked.

Millie Bobby Brown Instagram Stories. Photo: @milliebobbybrown/Instagram
Millie Bobby Brown Instagram Stories. Photo: @milliebobbybrown/Instagram

RELATED: Olivia Rodrigo Debuts Her Defiant New Single And Music Video ‘Good 4 U’

Rodrigo also shared Brown’s dancing, adding, “OMG I LOVE YOUU.”

“Good 4 U” is Rodrigo’s third single from her yet to be released debut album Sour.

Rodrigo will be the musical guest on “Saturday Night Live” on May 15 episode.

“SNL” airs Saturdays at 11:29 p.m. on Global.