For Heidi's first bash, she wore a costume with a vaguely S&M vibe—spikes, patent leather—and two Pippi Longstockings braids.
It's clear that Heidi is in a Halloween costume, but looking at this, you'd have no idea how committed she would become to the art of dress-up.
2001: Lady Godiva
Heidi leveled up by quite a bit for her second Halloween bash, making her entrance on a horse as Lady Godiva—an injured or dead one, given the blood dripping from her mouth.
While she wore a floor-length blonde wig and a sparkly white bodysuit, it was conservative by Lady Godiva standards. Legend has it that the English noblewoman rode her horse buck naked through town.
2002: Betty Boop
Year three of the model's Halloween hosting gave us scary Betty Boop—scary because she wore fangs under her red pout.
The costume was simple yet striking. Most of the work of getting into character as the iconic cartoon was in the hair and makeup.
2003: Gold Alien
It's unclear what exactly Heidi dressed as in 2003. What's obvious is that she went full-out from her braids all the way down to her ~wild~ boots.
She had a gold shimmer all over her body and she even wore gold teeth.
2004: Red Witch
In 2004, Heidi arrived at her party dressed as a scantily clad witch with scarlet hair. Her makeup was amazing, as usual. She also kindly gave a skeleton a piggyback ride on her way in.
The model had a whole "fly into the party like an actual witch" thing planned, but she ended up getting stuck in her harness, which undid the witch illusion.
Heidi loves a good stiletto boot to go with her Halloween costume, and in 2005, they were a black patent leather version that went to mid-thigh.
For her vampire look, she had on fangs, an enormous, curly wig, and a bleeding heart pinned to her corset dress.
2006: Forbidden Fruit
Heidi was concealing a pregnancy when she showed up to her party as a giant apple with a snake wrapped around it.
"The problem with that was that I was so big, I couldn't fit into a car, so I had to get a convertible at the last moment just so I could get to the party," she told the New York Post. "I couldn't drink water because my arms didn't reach my face, I couldn't even sit. That wasn't so much fun—I didn't fully think that one through!"
After such an ordeal with her apple suit, Heidi showed up the next year in a more relaxed look: a cat bodysuit.
She had her kitty claws out, but to the New Yorker, she looked a bit like a giant subway rat.
2008: Goddess Kali
Heidi said that her assistant had come up with the idea for this elaborate costume. "My husband and I were in India last year, so she said, 'Why don't you do an Indian goddess? Like a scary Indian goddess?' And I said 'OK!'"
Heidi and then-husband Seal twinned as two crows. While the costumes made the couple look like monster-size birds, the getups weren't at all practical.
"It was bad. My husband was driving and he could hardly see anything," Heidi said. "When you have a beak on, you can't talk to anyone, you can't really drink. It's not a good costume." Noted!
Heidi's superhero bot suit combined Iron Man's metallic armor with Mystique's boldly colored skin and hair.
Heidi described the costume as being "larger than life" and she was being literal when she said that. In her stilt-like boots, she towered over everyone at the party.
2011: "Bodies" Cadava
Remember the exhibition that went around the world and everyone went to see even though it featured the preserved remains of actual people? Heidi looked like a part of that traveling exhibit when she showed up to her first of two Halloween parties, this one in Las Vegas.
"It's kind of like a dead body with the first layer of skin ripped off," Heidi explained. "It's basically like me naked." She said that she called this costume the "visible woman."
For her second Halloween party of 2011, in New York City, Heidi and Seal arrived as apes.
The makeup took nearly six hours to apply, she said, and included fake breasts. She and Seal looked like they were so in love, but just a few months later, they announced their split.
Heidi teased her Halloween costume for 2012 — she was planning to go as Cleopatra — but ended up postponing the party out of respect for the victims of Hurricane Sandy, which hit just before Halloween.
When she finally had her party in December, she showed up in an improved version of the costume she had previewed. After a few years of being "ugly," she wanted "something really pretty and sparkly for a change," she told Us Weekly. There were hundreds of crystals on her face that were applied individually.
2013: 95-Year-Old Heidi
"When I was a 95-year-old version of myself, I spent a lot of time getting the details right, down to the varicose veins and the eye lenses to make it look like I had cataracts," Heidi told the New York Post. "No one recognized me, and I almost had to tell everyone to let me into my own party!"
Once she made it into her party, she had a rocking chair and a cane for when she got tired of all the standing.
After five hours in the makeup chair, Heidi metamorphosed into a butterfly for her 2014 Halloween party. She chose the butterfly costume because "someone very special to my heart called me a schmetterling [German word for butterfly], so I wanted to be a butterfly this year," she told E! News. "They're just so pretty and colorful and I used to love painting butterflies.
2015: Jessica Rabbit
Heidi raised her own makeup record to 10 hours in 2015 when she became Jessica Rabbit. A team of artists applied prosthetics not just to her face but her chest and rear (which made her too big to fit into her car, according to the New York Post's spies).
She looked utterly unrecognizable but entirely like Jessica Rabbit. Only Heidi could pull this off.