"YEEEES!"

That was how supermodel Behati Prinsloo responded to finding out she'd be opening up the Victoria's Secret Fashion Show. As the show draws near, it's time to check out some behind-the-scenes footage of the angels trying on those spectacular wings.

Cameras captured the fittings for the 20th annual collection, which frequently require meticulous adjustments. Executive Producer Monica Mitro refers to this stage as "the most important part of the collection."

"We are in the stage of fittings right now, which is a very crucial part of the collection," she explains. "We are seeing the models for the first time in their outfits, and we're letting them walk, and rehearse. The artisans are here, making sure their wings work."

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"Once those light-up wings go on stage, I will breathe a huge sigh of relief," says fashion designer Marian Hose, and there is joy in the models’ and creatives’ demeanor as they finally start to see the elaborate wings and lingerie come together.

At one point, model Gigi Hadid gets ecstatic over her fantastical butterfly outfit that is paired with green lingerie.

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"It's very important, especially today, to make sure that it feels right, and in the right place," the 20-year-old says of the fitting process.

Gigi joins Kendall Jenner as a model for the 2015 Victoria's Secret show in New York City, which will air on CBS Tuesday, Dec. 8.

WATCH: An Inside Look at How the Most Extravagant Victoria's Secret Angel Wings Ever Are Crafted

Now that you've seen the models get their wings, watch those wings being created in the video below.