Spider-Man: Across the Spider-Verse is a big escalation from the first movie. Last time out, we mostly hung out in Miles Morales' home dimension--but now, Miles is going all the way down the multidimensional rabbit hole, and he's going to find some things he really doesn't like down there.

　　Warning: This article contains major spoilers for Spider-Man: Across the Spider-Verse, including the full details of how it ends.

　　Across the Spider-Verse makes its intentions known right from the start, with a lengthy opening sequence that takes place in Gwen's universe, Earth-65. We get Gwen's backstory, with the tragic tale of her universe's Peter Parker, and how his death eventually led her to the cross-dimensional Spider-Society.

　　Then we catch up with Miles, who hasn't seen any of the other Spider-folks in over a year. He encounters and fights a new villain named The Spot, who has dimensional portals on his body, and not long after that, Gwen shows up. She's after The Spot, but visits with Miles while she's there. She tells Miles he's not allowed to be in the Spider-Society, then tracks The Spot to a dimension where Earth is dominated by an extremely awesome Mega City called Mumbattan (that's a portmanteau of Mumbai and Manhattan).

　　Miles sneakily follows her through a dimensional portal and ends up fighting alongside Gwen, Spider-Woman Jessica Drew, Spider-Punk, and Spider-Man Pavitr Prabhakar as they face off against The Spot in Mumbattan. The battle results in a sort of draw, as The Spot gets what he wants, but the Spider-People manage to save everybody. However, they may have saved too many, it turns out. We'll circle back to that.

　　Since Miles is already with them, the gang brings Miles back to Spider-Society HQ in Neuva York, 2099. Here we meet Spider-Man 2099, Miguel O'Hara--the boss of the Spider-Society and an all-around cranky guy. Miguel explains that Miles is the catalyst for all sorts of multiversal chaos, because he was bitten by a radioactive spider that wasn't from his home dimension--he's from Earth-1610, and that spider was from Earth-42.

　　The consequence of that, Miguel says, is that that spider's home dimension has no Spider-Man, and that the Peter Parker from Miles's world, who died in an early scene in the first movie, would have lived and defeated Kingpin during that scene had that spider not bitten Miles. And so, in essence, all this Spider-madness traces back to Miles--and that is why he wasn't supposed to be a part of the Spider-Society.

　　Miguel then describes how every Spider-person has to go through essentially one or more of the same group of personal tragedies--specifically the deaths of a parental figure (like uncle Ben), a love interest (like Gwen/Peter), and/or a police captain the person is close to (like both Gwen's and Miles's fathers). In Mumbattan, Miles saves Pavitr's girlfriend's dad, police Captain Singh--this was supposed to be Pavitr's first big tragic moment. And Miguel says that because Singh is still alive, Mumbattan's dimension might unravel.

　　To keep Miles from causing any more perceived problems, Miguel wants to lock him up until his dad, a police lieutenant about to be promoted to captain, is murdered. Miles goes on the run in a delightful chase sequence through the Spider-Society building, before attempting to use the "go home machine"--which detects which dimension you belong to and sends you there.

　　But instead of sending him home to Earth-1610, the machine drops him in Earth-42, the reality his spider was from that has no Spider-Man. Miles doesn't realize he's in the wrong place at first, but then he sees his Uncle Aaron, who died in the last movie. He tries to play it cool, but Aaron immediately realizes he's the wrong Miles--and moments later he's tied up and facing the Prowler. But this time, the Prowler isn't Aaron. In this dimension, Miles is the Prowler. And he's got a very bad and sinister vibe.

　　Gwen, recognizing where Miles ended up, also decides to take matters into her own hands, going rogue to assemble a team of Spiders (including Spider-Ham, who had been absent to this point) to invade Earth-42 and save Miles. And that's when Across the Spider-Verse hits us with the "To Be Continued."

Does Spider-Man: Across the Spider-Verse have a post-credits scene?

What does "Beyond the Spider-Verse" even mean?

　　Does that preclude any sort of MCU shenanigans in the next movie? Nope. Across the Spider-Verse directly references the MCU twice, first when Miguel obliquely mentions the events of Spider-Man: No Way Home and then again when we see Donald Glover's version of Uncle Aaron in a Prowler suit locked up at the Spider-Society. It's been a minute, so in case you forgot: Glover played Davis in a brief appearance in Spider-Man: Homecoming.

　　The MCU never has any real interjections into the plot, though, and Sony has shown over and over that they want to keep full creative control of as much of their Marvel stuff as they can. That likely precludes any kind of significant MCU story crossover, but cameos and Easter eggs on the level of Donald Glover's appearance in this film (two scenes and a couple lines) should still be possible.

　　Phil Owen on Google+