The Stranger Things star, 44, wore a camouflage jacket, blue shirt and black pants while Allen, 34, opted for a black coat while she carried a Chanel purse. Harbour’s father, Kenneth, was also photographed with the pair heading to the party.
Allen shared photos from Harbour’s SNL sketch parodying a SoulCycle class, during which the host wore a sleeveless shirt and showed off his muscular arms. In a zoomed-in photo of Harbour’s bicep, Allen captioned her image: “Mine.”
Harbour was previously spotted with Allen in August while he was filming Black Widow in London. The two attended the performance of The Lehman Trilogy at the Piccadilly Theater and then dined at a restaurant, according to E! News.
Harbour, who previously dated Fantastic Beasts star Alison Sudol, has been linked to Allen since they sparked dating rumors in January when they attended the BAFTA Tea Party together.
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“I’ve always had a boyfriend. I don’t at the moment. I’m single for the first time since I was about 15,” Allen said on the How to Fail with Elizabeth Day podcast.
Allen was previously married to builder and decorator Sam Cooper, 41. They married in 2011 and announced their split in 2016 before finalizing their divorce last June. Allen and Cooper share two daughters, Ethel, 7, and Marnie, 6.