Jennifer Aniston and Justin Theroux Attend Katy Perry’s Surprise 40th Birthday Party for Orlando Bloom

Girlfriend of the year? Katy Perry threw her boyfriend, Orlando Bloom, a surprise 40th birthday party in Palm Springs, California, on Saturday, January 14. Jennifer Aniston (who shares mutual ex John Mayer with Perry) and her husband, Justin Theroux, were among the many celeb attendees.

The "Rise" singer, 32, documented the celebration at the Colony Palms on her Instagram Story, where she posted a video of the Pirates of the Caribbean actor blowing out the candles on his two-tier birthday cake topped with an owl decoration. The clip also revealed that guests wore sweatsuits adorned with Bloom's face at the bash organized by celebrity party planner Mindy Weiss.

Bloom shared a sweet picture with his mom, author Sonia Copeland Bloom, during the party. "Best gift ever surprise visit from me mum," he captioned the Instagram shot of Sonia giving him a big hug.

best gift ever surprise visit from me mum ?

A post shared by Orlando Bloom (@orlandobloom) on

Perry debuted her newly dyed honey-blonde hair at the soirée. She was photographed arriving wearing a black blouse and a pair of round glasses. Once inside, she and her beau, who started dating in May 2016, changed into the funny, personalized onesies, according to photos shared on fan social media accounts.

TV personality/pop artist Sham Ibrahim and singer Katy Perry pose for a photo on Jan. 14, 2017, in Palm Springs, CA. Tara Ziemba/Getty Images

British talk show host Amanda de Cadenet also rocked the Bloom hoodie. She posted a selfie on Instagram, writing, "Partying in my @orlandobloom Birthday Suit .. #Happy 40th to my sweet friend. Such a treat to celebrate your life."

Last October, Perry celebrated her birthday with Bloom at an equally fun-filled '50s sock hop–theme party.

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