London, UK - Olivia Rodrigo took her Halloween festivities across the pond as she celebrated with a star-studded group of friends in London.

The 20-year-old singer was spotted out on Friday night as she kicked off Halloweekend in London.

Per snaps from the party shared on social media, Olivia rocked an all-black ensemble paired with black cat ears.

Joining her were Heartstopper stars Joe Locke, Kit Connor, and Tobie Donovan, as well as Enola Holmes actor Louis Partridge.

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Joe took to Instagram on Sunday to drop a photo dump from the festivities, which included a selfie alongside Olivia.

The get him back! artist also documented her London adventures on her own social media, sharing a new TikTok with long-time friend and fellow musician Conan Gray on Saturday.

The UK outing comes shortly after Olivia's continued promotion of her sophomore album, GUTS, in the US, as the Grammy winner recently stopped by Jimmy Kimmel Live to discuss the record and perform the fan-favorite track ballad of a homeschooled girl.

Olivia is set to soon travel around both North America and Europe on the highly-anticipated GUTS World Tour, which kicks off in February.