Billie Eilish celebrated the 1-year anniversary of Happier Than Ever with a surprise acoustic performance in front of an intimate crowd.

The “Bad Guy” singer and her music partner and brother, Finneas, performed four songs Friday at the famed record store Amoeba Music in Hollywood. According to Variety, the impromptu performance was limited to 500 ticket holders, who lined up the store hours before the Grammy-winning artists were set to appear.

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The outlet reported that the set started with “Billie Bossa Nova” before moving on to “TV”. Eilish then asked the crowd to chime in on what song they wanted to hear next. The boisterous crowd went back and forth but ultimately settled on “Getting Older”. Eilish closed out the set with “Happier Than Ever”.

She later told the crowd, “You guys are just the best. It’s been the most amazing year, and you’ve been so sweet and respectful about this album, and I just love you!”

Happier Than Ever is Billie’s second studio album. It was released exactly one year ago on Saturday, which also marks Finneas’ 25th birthday.

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Those lucky enough to nab tickets for the short set also got to take home an autographed Eilish poster along with a Happier Than Ever on vinyl and a wristband. Amoeba Music announced Eilish’s appearance Friday at 9 a.m. for a set scheduled at noon, and fans raced to the store to nab tickets. The event quickly sold out.

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The surprise set comes just days after Billie released two surprise songs — “TV” and “The 30th”. She had previously performed “TV” live on tour last month. The tracks were released from Eilish’s new two-track EP, Guitar Songs, which is now available across all digital streaming platforms.

Fans first heard “TV” as an unreleased track performed at the Manchester stop of Eilish’s Happier Than Ever tour on June 7.

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