After four-and-a-half seasons of questions prompted by “Stranger Things,” in Volume 2 of the show’s fifth and final season, creators Matt and Ross Duffer offered answers aplenty, while also setting up the potentially tragic stakes of the series finale.

In Volume 2’s “The Bridge,” it is revealed that the Upside Down is actually part of a wormhole connecting Earth and The Abyss, another dimension occupied by Vecna ( Jamie Campbell Bower ), the Demogorgons, Mindflayer, and more.

Stranger Things season 5 part 2 was certainly putting the science in science fiction. The latest batch of episodes does a lot of heavy lifting in explaining the

Matt and Ross Duffer tease what's in store.