It's not a bird. It's not a plane. But it's not exactly your typical McDonald's restaurant, either.
It's CosMc's, a mysterious new spinoff restaurant from the world's largest hamburger chain that has caused quite a stir on social media and across the Chicago area.
According to a spokesperson, CosMc's is McDonald's new "small-format, beverage-led" concept restaurant set to open this week in Bolingbrook as part of a "limited test."
"Inspired by nostalgia and powered by a menu of bold, refreshing beverages and tasty treats, CosMc’s is landing earthside for us humans to enjoy," the company said in a release.
CNBC reported the company's CEO Chris Kempczinski spoke about the idea in the burger chain's second-quarter earnings call over the summer.
"CosMc's is a small-format concept with all the DNA of McDonald's but its own unique personality," he said.
The new location is set for a "soft open" on Friday, with celebrations planned this weekend. However, Sky5 photos and video from the spot Thursday showed rows of cars lining up for multiple drive-thru windows.
Here's what we know about the restaurant so far.
CosMc's Food Menu
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"CosMc’s seamlessly blends brand-new, otherworldly beverage creations with a small lineup of food, including a select few McDonald’s favorites – all designed to boost your mood into the stratosphere, if only for a few moments," the company said.
Although the menu is set to contain some McDonald's staples -- like Egg McMuffins sandwiches and M&M McFlurry -- other items on the menu include the Creamy Avocado Tomatillo Sandwich, Spicy Queso Sandwich, Savory Hash Brown Bites, Pretzel Bites and a charcuterie-style Snack Box. On the sweet side, the menu includes a blueberry lemon cookie sundae and caramel fudge brownies, the Chicago-based chain said.
CosMc's Beverage Menu
The restaurant touts CosMc's drink menu as "brand-new, otherworldly, beverage creations." A sneak peek of the beverage menu shows it includes specialty lemonades and tea, espresso drinks, blended beverages and cold coffee, including a Sour Cherry Energy Slush, a Tropical Spiceade and S'mores Cold Brew.
There will be options for customers to add things like boba, flavored syrups, energy boosters or vitamin C shots and more, the restaurant said.
Why is it called CosMc's?
The restaurant appears to be based on a vintage McDonaldland mascot named CosMc, an alien character who appeared in ads in the late 1980s and early 1990s.
McDonald's had teased plans to test out the new kind of restaurant over the summer, but recent images showing a mysterious building in Chicago's suburbs with signs of the golden arches led to much speculation.
The move is the latest vintage revival for the Chicago-based fast food chain.
Most recently, the company announced another throwback collectible would be coming back. Beginning next month, "McNugget Buddies" — friendly collectors items in the shape of chicken nuggets, first introduced as part of Happy Meals more than 25 years ago — will be part of a new McDonald's meal called the "Kerwin Frost Box," the chain said.
When is it opening and where?
Roughly 10 locations are expected to open by the end of 2024, including in the Dallas Fort-Worth and San Antonio metro area, the chain said.
The Bolingbrook location is set for a soft-opening Friday, with celebrations planned over the weekend, a spokesperson said.
