Inside Heidi Klum's Halloween Costume Fitting to Become The 'Ultimate Male Fantasy'

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For Halloween this year, Heidi Klum is going to become "the ultimate male fantasy" -- although that might not be quite as sexy as it sounds.

Speaking with ET at the costume fitting, the America's Got Talent star teased her upcoming outfit, and revealed that getting into her costume will take over nine hours, mostly due to all the prosthetics!

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"I basically had to be casted head to toe because there will be lots of body parts," Klum explained. "The cast process took about four hours to do."

Klum posted a few photos of the body casting to Instagram three weeks ago, and by the looks of all the purple goo covering her from head to toe, it looks like that was a long, uncomfortable four hours. That is some serious commitment to costuming!

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The 42-year-old supermodel and TV personality is teaming up with GSN's horrifying new game show Hellevator for her annual star-studded Halloween party at Lavo nightclub in New Jersey. But if you get an invite, you better put some effort into your look.

"You have to have a real outfit, otherwise you will not get in," Klum warned.

You can't blame her for having high standards when it comes to costumes! For years now Klum has pulled out all the stops on Halloween, dressing up in some of the most elaborate (and often super creepy) costumes imaginable.

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While we might have to wait to see what kind of complex transformation Klum will pull off this year, we've already gotten an eyeful of other celebs' elaborate Halloween outfits. Check out the video below for a look at some stars who really went all out to get into the spooky spirit.

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