Why Is Heidi Klum Preparing for Halloween in July?

Heidi Klum really loves Halloween, so much so that ― although the holiday is three months away ― she's already working on her costume.

The "America's Got Talent" host, whose annual All Hallows Eve bash has become a hot ticket for Hollywood types, posted a photo Monday to let her fans know that her preparations for Heidiween 2013 are already well underway.

"Started working on my Halloween costume!" the 40-year-old German model wrote on Instagram, along with a decidedly unglamorous photo of her face and shoulders covered in a gooey gray paste, an apparent start of a prosthetic mask.

An artist is seen shaping Klum's nose, so the mom of four can breathe easily come October 31.

While the "Project Runway" guru gave no indication as to what she will dress as this year, we have come to learn that there are no limits. Some of her over-the-top costumes over the years include a real hair (and anatomically correct!) chimpanzee, a skinless human body (that arrived on a gurney), and an 8-foot-tall red and purple alien.

Another mystery remains as to whether or not she will go for a couples costume this year. While married to Seal, they would typically coordinate their looks, but then that whole divorce thing happened. At last year's bash ― which was moved to December due to Hurricane Sandy's impact on New York City ― she was already dating her bodyguard squeeze Martin Kristen, but she came dressed as Cleopatra and he was Batman.

Now that they're an established couple, we expecting them to step up their game.

Check out Heidi's most memorable Halloween costumes so far...

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