Most "Stranger Things" viewers probably didn't give a lot of thought to the science behind the Upside Down. But naturally, Bill Nye did, and the star of Netflix's new "Bill Nye Saves the World" runs it down for us in a new short video posted Wednesday.
With a little help from the "Stranger Things" kids' own science teacher, Mr. Clarke, Nye sketches out the theory of multiverses (can another version of Barb still be around in one of them?), and somehow brings it all back to Eleven and her Eggos.
This isn't the first time another Netflix show has collided with "Stranger Things" in a video. The cast of the new season of "Mystery Science Theater 3000" recently riffed on a scene from the show involving police chief Hopper and some morning Schlitz and smokes.
"Bill Nye Saves the World" is now available on Netflix. "Stranger Things" will return to the streaming service on Halloween, Oct. 31, 2017.