Derek and Julianne Hough know how to class up a party.
The professional dancer siblings hit up actress Nina Dobrev's birthday party on Friday decked out as Ryan Gosling and Emma Stone's characters from their hit musical rom-com La La Land.
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In a sweet snapshot of their spot-on costumes that Derek posted to Instagram, he paid his sister a major compliment, calling her "the modern day Ginger Rodgers."
It appears the former Vampire Diaries star's b-day bash was entirely La La Land-themed, and everyone who attended the fancy bowling alley soiree rocked some elegantly retro attire to celebrate -- including The Path's Aaron Paul, who looked dapper as ever in a black and blue suit ensemble.
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Julianne also made sure to snap a cute selfie with her friend the birthday girl, who couldn't have looked classier in a sleeveless powder blue gown.
Earlier this month, the Los Angeles-set modern-day musical picked up seven Golden Globe awards, which Gosling said was "a wonderful surprise" while walking the red carpet at the film's Paris premiere shortly after the awards show. Check out the video below to hear more.