At the same time, Peter has his own issues with energy, because his arachnid hormone levels are spiking, giving him major headaches and the ability to shoot web fluid from his wrists instead of his suit. He wants nothing more than to tamp down his powers, to return to the abilities that he knows well. And it’s imperative he does this before the entity gets to MJ, who still doesn’t know who he is.

There is, of course, a lot more, some of which I can’t tell you; Sadie Sink has spent the last year dancing around questions about her role in this movie. “Brand New Day” is the fourth in this particular series of Spider-Man movies, and it feels like a cap on the growing-up arc that this iteration of the character has gone through. If “Homecoming” was about adolescence, and “Far From Home” was about growing through the loss of a mentor, and “No Way Home” was about taking responsibility for your actions (and also, college applications), then this is, in part, about deciding to accept your adult powers, even when they scare you.

It is not, unfortunately, nearly as fun as the previous few films, though that may just come with the territory. Much of the lighthearted comedy that made the other movies so amusing is gone, largely because Peter’s relationship to Ned and MJ has changed drastically, which means the bantering chemistry between Holland, Batalon and especially Zendaya is mostly absent. In its place is an emotional heaviness, which compounds in some of the film’s other plot threads. (Thankfully, Florence Pugh shows up a few times as Yelena Belova, and she is a pure delight.)

The film is also bogged down by the same thing that has caused late-stage Marvel Cinematic Universe films to sag: the weight of tying all of the stories together. For instance, if you’re not a walking encyclopedia of M.C.U. lore — or didn’t watch “Daredevil” Season 2 and “Daredevil: Born Again” Season 1 and the two-season “Punisher” TV show and the “Punisher: One Last Kill” Marvel TV special — you might not know who Frank Castle is or why he and Peter know each other, which seems like an awful lot to expect of your audience.

Spider-Man has been tied into the M.C.U. since he appeared in “Captain America: Civil War” (2016), thanks to a deal between Sony Pictures Entertainment and Walt Disney Studios (which owns Marvel Studios), and he’s in several “Avengers” movies. Although other M.C.U. characters crop up in the stand-alone Spider-Man movies, sometimes with substantial roles, the films have still mostly felt like character-driven features about Peter and his friends. Even “No Way Home,” with its many winking ties to other movies, was mostly about various generations of Spider-Mans (Spiders-Men?), not really the M.C.U.’s main arc.