Spider-Man: Far From Home packs quite a few punches within its two-hour runtime. One of its major Easter eggs (which was already revealed in a previously released teaser) is the mention of a multiverse — a realm in which an infinite amount of alternate worlds subsist. This concept isn't all that alien to anyone familiar with the superhero genre, especially Marvel. But the most recent installment of Spider-Man is the first time a character in the MCU has blatantly given a number to the onscreen reality as we know it.
According to Quentin Beck/Mysterio (Jake Gyllenhaal), the world that we're conversant with is Earth-616. If you're keen on Marvel comics, that number should ring a bell. Earth-616 is the reality in which most of the main storylines take place and where our favorite heroes — Spider-Man, Iron Man, Captain America, Black Panther, etc. — have valiantly fought. It's also where the same historical events that we know of — i.e., World War II and the Cold War — have occurred. Simply put, Earth-616 in the comics is based on our Earth.
Mysterio also says that he's from Earth-833. This is yet another nod to the comics, as Earth-833 is the home of William Braddock — aka Spider-UK — who is an England-based iteration of the web-slinging hero. Mysterio's remark about that particular Earth is a pretty clever toss-in, considering some of Spider-Man: Far From Home's biggest scenes take place in London. But any other connection beyond a slick reference for comic-book fans to catch and cradle remains a mystery — or perhaps a hint at future MCU plotlines.
Although this film is the first time Earth-616 is conspicuously identified, there have been previous allusions to it. In 2013's Thor: The Dark World, Dr. Erik Selvig (Stellan Skarsgard) — who's admitted into a mental institution following the events of 2012's The Avengers — gives lectures to his fellow inmates about the convergence of the Nine Realms within the cosmic aura Yggdrasil. He's speaking in front of a chalkboard covered in seemingly nonsensical words and scribbles, but if you look behind him (at 1:22 in the clip below), you'll see "616 universe" written out.
The multiverse is also referred to in Doctor Strange when the Ancient One (Tilda Swinton) takes Doctor Strange (Benedict Cumberbatch) on a projected journey through the cosmos. "You think this material universe is all there is?" she says. "Who are you in this vast multiverse, Mr. Strange?" Hopefully, this is something the film's sequel will dig even deeper into.
Now, that being said, there is a bit of a hiccup in all this. The MCU is already designated as Earth-199999, which distinguishes it from the comics. And the latest Spider-Man movie doesn't totally shoot down the idea that the MCU can keep that alias (I'm trying really hard not to spoil anything here, people). But whether or not the MCU is still indeed Earth-199999 or if it's taking on the official Earth-616 title as a connection to the comic book is something you'll have to decipher yourself when you see Spider-Man: Far From Home, which is out now!