The actor slipped out of her sparkly black Miu Miu gown and into an oversized white suit—maybe not the most practical look with a new puppy.

Sweeney is set to star in "Scandalous," a film about Kim Novak's life directed by this year's Met Gala cochair Colman Domingo.

Sydney Sweeney did not take Sully to the actual Met Gala earlier in the evening, of course. The actor walked the blue carpet in a fitted black Miu Miu dress, which featured a keyhole cutout at the neckline and an elaborate gold broach.