Ariana Grande wins blue ribbon from Jennifer Coolidge for Best in Show costume: 'F---ing great'

Call off the dogs — Halloween's winners have been found, according to one not-quite-impartial judge.

Ahead of the spooky holiday, Ariana Grande and her Victorious costar Elizabeth Gillies got into the spirit by sharing their pitch-perfect take on the dog show mockumentary Best in Show.

In a joint Instagram post on Friday, featuring images they said they shot in May, Grande and Gillies not only dress as characters from the film — complete with wigs, prosthetics, and costumes — but also recreate scenes from it.

As fans of the 2000 cult classic know, Best in Show was directed by Christopher Guest and features an all-star cast including Eugene Levy, Jennifer Coolidge, Parker Posey, Fred Willard, Linda Kash, Jane Lynch, Catherine O'Hara, and Larry Miller. Shot in fly-on-the-wall style, it offers a hilarious (and fictionalized) look at the highly competitive and cutthroat world of dog shows.

In their recreations, Grande tackles the role of trophy wife Sherri Ann Cabot (Coolidge's character), as well as the roles played by Levy and Kash. Gillies meanwhile offers imitations of the characters played by Lynch, O'Hara, and Miller.

Doane Gregory/Online USA/Getty Jane Lynch as Christy Cummings and Jennifer Coolidge as Sherri Ann Ward in 'Best in Show.'

Coolidge, who previously starred in Grande's "Thank U, Next" music video as her Legally Blonde character Paulette, was one of many stars who weighed in on the spot-on Instagram post. "This is f***ing great. I was gonna go as the young boy's pet weasel from 'The Watcher' but now I think I'm gonna go as @arianagrande's dog Toulouse," she wrote (simultaneously plugging her new Netflix show).

Fellow celebs like Katy Perry, Victoria Justice, Rachel Zegler, and Eliza Bennett also applauded Grande and Gillies' efforts, which you can check out in the post above.

See more of this year's best celebrity Halloween costumes.

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