Beginning Oct. 3, McDonald's will launch a new Happy Meal -- geared toward adults -- as part of a collaboration with streetwear fashion label Cactus Plant Flea Market, according to a press release.

"We're taking one of the most nostalgic McDonald's experiences and repackaging it in a new way that's hyper-relevant for our adult fans," said Tariq Hassan, McDonald's USA Chief Marketing and Customer Experience Officer. "

Just in time for Halloween. McDonald's is saving its freakiest toys for adults. McDonald's announced that it partnered with Cactus Plant Flea Market — a streetwear brand embraced by Kanye West and Pharrell Williams, among other high-profile fans — to repackage the Happy Meal "experience" for an older audience. The result of their collaboration is the Cactus Plant Flea Market Box: a Happy Meal-style offering packaged with one of four bizarre little figurines.

McDonald's is Launching a Happy Meal for Adults
McDonald's hopes to repackage the Happy Meal experience for a new generation of customers. (McDonald's)

Each meal comes with either a Big Mac or 10-piece McNuggets, fries, and a drink. Inside the box, customers will also find one of four figurines — including Grimace, Hamburglar, and Birdie — each created in the image of Cactus Buddy, the four-eyed smiley-face mascot for Cactus Plant Flea Market. Cactus Buddy, too, is among the four available figurines.

The box has also been designed in the streetwear brand's "signature style," according to McDonald's, featuring imagery of a four-eyed Grimace visiting a McDonald's alongside Cactus Buddy.

McDonald's is Launching a Happy Meal for Adults
Grimace and Cactus Buddy — the signature mascot for Cactus Plant Flea Market — are pictured on the side of the Cactus Plant Flea Market meal boxes. (McDonald's)

According to McDonald's, those who purchase a Cactus Plant Flea Box via the McDonald's app will be automatically entered into a weekly sweepstake to win exclusive collaboration merchandise, including T-shirts, other apparel, and a piece of furniture called the "Grimace Chair."

It's unclear when the promotion is scheduled to end, but the packaging imagery hints that the boxes won't be available for very long.