Billie Eilish surprises fans with new song Lost Cause and new music video

Billie Eilish in her new music video for Lost Cause. Photo / Interscope Records

Billie Eilish has surprised fans with a new song and video.

Lost Cause depicts a sassy side of Eilish, and gives fans a taste of what we can expect from her new album Happier Than Ever.

Eilish and an entourage of her friends dance together throughout the video. She sings about realising an ex-boyfriend wasn't so cool after all.

A carefree Eilish sings: "I sent you flowers / did you even care / you were in the shower and left them by the stairs."

She weaves in other subtle insults jabs at the subject of the song later in the track.

"I used to wish you were mine, but that was way before I realised someone like you would always be so easy to find," she says, expertly dissing her ex.

While the artist has not let slip who the song is about, fans have speculated her album will be about her ex-boyfriend Brandon Q Adams. He featured in the star's documentary The World's a Little Blurry.

Fans are convinced the new album will tell the story of their breakup, Seventeen reports.

The song has fans even more excited for her second album, slated for release on July 30. The record has 16 tracks, including the previously released singles My Future, Therefore I Am, and lead single Your Power.

If the previous releases are anything to go by, fans can surely expect a mix of emotional ballads and catchy beats from the 19-year-old.

She graced the cover of British Vogue in May, and wore corsets created by top fashion designers. During the interview, she shared her intention behind the photoshoot.

"It's about taking that power back, showing it off and not taking advantage with it," she shared.

The popstar makes it clear she is in charge of her creative choices: "I'm not letting myself be owned anymore."