It took nearly five years, but Tom Holland's Spider-Man is finally back, and he just climbed to unprecedented new heights. Spider-Man: Brand New Day has been making waves for all the right reasons: The film's reviews are nothing short of stellar, while early projections suggest it could become the wall-crawler's highest-grossing project ever, even surpassing the likes of No Way Home. Better yet, many characters from the wider Marvel Cinematic Universe also play a key role in the web-slinger's latest adventure.
Promotional materials and trailers had already revealed that anti-heroes like Hulk and the Punisher would help Peter Parker (while also creating a bit of havoc along the way), and that organizations like the Hand and the Department of Damage Control would also be involved. However, Marvel and Sony had even more surprises in store, and some of them are integral to the movie's story. One of the plot points audiences didn't know about beforehand is "VMax," a MacGuffin tied to the arc of a very specific (but important) character.
However, before we begin and break down what VMax really is, consider this an official warning: There will be MAJOR spoilers for Spider-Man: Brand New Day ahead. If you don't want any surprises ruined, it's best to turn back now, watch the film, and return once you discover everything Marvel's latest title has to offer.

If you're still here, I must assume you know that both Sara and Jean Grey appear in Spider-Man: Brand New Day. If not... well, surprise! Not only are the siblings a part of the friendly neighborhood hero's latest film, but the two are looking for something named "VMax," so what really is it?
What truly is VMax?
Since the opening moments of Spider-Man: Brand New Day, we see Jean Grey use her telepathic and telekinetic abilities to attack a facility of the Department of Damage Control (DoDC), all in the hope of finding something called "VMax."
Not even Jean herself knows what VMax really is, and when Spidey learns about Jean's true intentions, he is clueless as well. The wall-crawler even asks the film's antagonist and the head of the DoDC, William Metzger, whether he has some insight into what VMax truly is, but the villain claims he doesn't know either. At first, audiences are led to believe that Metzger is simply lying to keep the truth hidden away. However, we eventually learn that (just this once) he was telling the truth.
So how did Jean learn of VMax in the first place, if apparently no one else in the MCU knows what this MacGuffin really is? See, Jean had an older sister named Sara Grey who also happened to have telekinetic and telepathic abilities. The two grew up in foster homes, and even when they finally found a home, their adoptive mother ran away upon finding out the two were mutants with special abilities.
To make matters worse, the DoDC has been hunting mutants all throughout the MCU, even appearing in projects such as Ms. Marvel and Wonder Man and getting into conflict with their respective main characters. Unfortunately, the organization not only learns about Sara Grey but also manages to capture her. It is then that Metzger traps Sara in a small room and starts experimenting on her with the hopes of discovering the key behind her powers and replicating it in other human beings.
The relentless nature of the experiments brings Sara to the point of death. But before she passes away, she uses her telepathic powers to tell Jean that she should "seek VMax." That's why the latter has been attacking DoDC facilities: In the hopes of learning what her sister really meant.
Ultimately, Jean Grey herself is captured and taken to the same room where her sister was once held captive. Jean then looks to the ceiling, and it is then that the truth is finally revealed: "VMax" is short for "Ventmax," the brand of the air conditioning vent in this prison cell.

Why did Sara Grey tell Jean Grey to find VMax?
It may be a little confusing why Sara would use the last of her powers to tell Jean to find... an air conditioning vent. However, there's a very good reason for this.
Sara knew she would die well before the DoDC accomplished its mission of replicating her powers. As such, it was logical to assume that the villainous organization would search for another test subject, and that would be none other than Jean Grey herself. With that in mind, Sara anticipated that Jean would be captured and brought to the same room in which she was held captive. But how do you escape such a place? Well, through the building's vents, of course.
Sara was trying to tell her sister that the air conditioning system was the only way to freedom. Maybe Sara herself didn't notice this small detail until it was too late, and she didn't want Jean to repeat the same mistake. "VMax" was never a cure, a weapon, or the facility where Sara was hidden away. It was simply a head start for Jean.
What makes this story all the more heartbreaking is that, when Jean finally finds "VMax," she understands that her sister didn't survive the DoDC's experiments. So even if this MacGuffin didn't end up being an unexpected key of sorts, it was definitely instrumental to the story of Spider-Man: Brand New Day.
Spider-Man: Brand New Day is out now in theaters.
