Heidi Klum has officially won Halloween.

After weeks of hints, including a series of Instagram photos and videos teasing the look, the 42-year-old model debuted her epic costume at her 16th annual star-studded Halloween party in New York City on Saturday.

PICS: Celebrities Dress Up for Halloween -- See All the Costumes! 

Klum dressed as Jessica Rabbit, donning the Who Framed Roger Rabbit character’s signature red dress and purple gloves at LAVO nightclub. She looked like a real-life cartoon, as prosthetics were used in the making of her over exaggerated features -- to the point that Klum was nearly unrecognizable!

ET was at the party and caught up with Klum, who's known for her elaborate Halloween costumes, on the red carpet after she made her entrance with a full-on, in-character performance.

“I’m feeling sexy today,” she said.

The model then told us that the process was quite the task. “[The transformation] started at noon,” she told ET around 11 p.m. “I literally finished and got right over here.”

WATCH: Inside Heidi Klum’s Halloween Costume Fitting

Though the process did take longer than Klum had initially expected, it was all worth it.

“It always takes longer because then we have lunch, and then I mess up the lips or some of the prosthetics come off,” she explained. “Then we had to glue the dress on. We didn’t know how much boobs to show or how high it should, how long it should be."

"My butt feels so funny! Driving over here was very interesting," she added.

Klum also noted that her boyfriend, Vito Schnabel, was not in attendance, as he had to get his rest in order to run the New York City marathon the next morning. “He had to go to sleep early tonight,” she shared. “He had a very good excuse.”

Her four kids -- Helene, 11, Henry, 10, Johan, 8, and Lou, 6 -- were also at home, but Klum says they did get to at least see photos of their mother’s costume.

“My kids have only seen it in photos, but we did watch the movie not too long ago so that they would know who I am,” she said. “It’s funny because they can never recognize me."

Klum wasn’t the only one dressed to impress at the party. Fellow model Gigi Hadid stepped out as Sandy from Grease, wearing an off-the-shoulder black cropped top, high-waisted leather pants and red heels.

Casper Smart and Jennifer Lopez were also in attendance. Both were dressed as creepy skeletons, complete with all-black ensembles and black-and-white face makeup.

Another standout was actress-model Emily Ratajkowski, who pulled out all the stops as Marge Simpson from The Simpsons.

Nicole Scherzinger also turned heads, rocking a vampire-esque ensemble complete with eerie contact lenses and edgy makeup.

WATCH: George Clooney’s Star-Studded Halloween Party

Following the event, Casper, J. Lo, and even more stars who were at the shindig, like Orange Is the New Black's Dascha Polanco and Ashanti, took to social media to share highlights from the spooktacular night.

Prior to the party, ET went to Klum’s costume fitting, where she teased that it was going to take nine hours to become “the ultimate male fantasy.” Watch the video below to hear more.

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Celebs Dress Up for Halloween 2015