With more than 200 credits on his resume, the prolific Blum had plenty of big-screen characters to pick from for this year’s costume, but he went with the one that recently went viral after the trailer dropped earlier this month.

The Universal Pictures film, directed by Gerard Johnstone from a script by Akela Cooper, centers on a robotic doll that is described as a “marvel of artificial intelligence.” Designed by a brilliant toy company roboticist named Gemma (Allison Williams), M3GAN can become friend and teacher, playmate and protector for the child she is bonded to. When Gemma becomes the caretaker of her orphaned 8-year-old niece Cady (Violet McGraw), she pairs the M3GAN prototype with Cady only to see the situation spiral out of control.

Judging by the trailer and early promotional materials, Blum nailed the costume down to M3GAN’S long blonde tresses and preppy ensemble. He started teasing this year’s installment early in the week, sharing that his costume was still “a big secret.” However, he inched closer to the big reveal early in the evening by showing photographic evidence of the makeover with his 154,600 followers. “It’s happening,” he wrote, followed by close-ups of his face with fresh coats of make-up.