Heidi Klum transforms into an eery biohazard experiment gone wrong arriving at her Halloween party in a semi-truck for the big reveal.

The supermodel had people guessing what she was going to transform into on Halloween as she sat storefront at Milk Studios in New York City getting her costume made while spectators watched from the sidewalk.

We took a guess she was a bionic woman as she was getting prosthetics placed but it turns out she was a biochemistry experiment gone bad — close enough.

Heidi was not the only celebrity to go all out for her yearly Halloween bash — Mariah Carey looked epic dressed as a young Tina Turner as her makeup artist Kristofer Buckle joined in on the fun.

Gerard Butler was spotted as the Phantom of the Opera as Karlie Kloss went with the old-time favorite costume and dressed as Dracula for the party.

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Coco Austin looked killer as Madonna wearing a replica of the infamous cone bra worn by the pop icon during her Blonde Ambition Tour — fun fact, the bra was created by French designer Jean Paul Gaultier for his 1980 catwalk but it didn’t become iconic until Madonna wore it during her tour in 1990.

Tana Mongeau as Unholy Pope and Drake as his Father at Poppy Halloween Party