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As the summer cinema season goes into full swing, there's a few films that have been exciting comic fans. One of those films is the upcoming Spider-Man: Brand New Day.
As the fourth entry in the Marvel Cinematic Universe's (MCU) Spider-Man series, Brand New Day has a lot of hype for many reasons. Spider-Man has always been one of Marvel's most popular characters in all forms of media. His status as a regular guy who just happens to have superpowers makes him unique and relatable in a world of billionaires and gods.
This series of films is also the first in the Spider-Man franchise to continue beyond its trilogy. The third film, Spider-Man: No Way Home set up an interesting situation where Peter Parker is forgotten by everyone. This gives Marvel the opportunity to do a bit of a soft reset. This means there's a lot of room for speculation from us fans.

The Trailers
The first trailer for the aforementioned film opens on Peter Parker (Tom Holland) looking down at his phone, watching his former friends, Ned (Jacob Batalon) and MJ (Zendaya), getting hyped for their new lives at MIT without him. It then switches to a montage of Peter seeing them out and about with a voice over of him reading a note which reveals the forgotten plot of the last film.
"And sometimes Spider-Man has to do the hard thing, even if it breaks Peter Parker's heart."
The Emotional Arc
This line sets up what will most likely be the emotional arc of the film. The montage shows that Peter has been his social and emotional well-being in favor of excelling as Spider-Man. This gives Peter a choice. Should he continue to let his identity as Peter Parker disappear or should he risk the safety of his friends by revealing his identity as Spider-Man?
Many have speculated about what Peter will do. Some say he'll keep it a secret for now while others claim he'll reveal it at some point during the film. The second trailer even shows him interacting with MJ as Spider-Man
In my opinion, unless the film wants to end on an emotional downer, Peter will need to reveal his secret. The trailer is clearly showing us that Peter is suffering as a loner. I think that his reveal will come at the end of the film, probably after the climax. This could set up a reconnection plot for a possible fifth film.

The Mutation Plot
The second half of the trailer primarily focuses on Peter's new transformation as Spider-Man. After speaking to Dr. Bruce Banner (Mark Ruffalo), it seems that he finds out that his spider DNA is mutating, leading to new abilities such as organic web shooting. An unknown narrator says:
"Spiders have three life cycles. When between cycles, it can leave the spider vulnerable to threats. And for those spiders who make it through, it amounts to a kind of rebirth"
This plot seems thematically aligned with the first. Peter is vulnerable after a major upheaval in his life. Coming into adulthood is hard for everyone, and it makes sense that a major life change would affect the hero similarly.

In real life, spiders have four life cycles. Assuming that the film is combining the egg and egg sac stage, this leaves us with the egg stage, the spiderling stage, and the adult stage. Peter's egg stage would have probably been when he first got his powers, and his spiderling stage has covered the past three films, which means he's most likely moving into his adult stage.
Many have noted that during the first two films, Spider-Man seemed to live in the shadow of his father figure, Tony Stark (Robert Downey Jr.). The spiderling stage is when spiders most resemble their parents, whereas the adult stage is where they must make their own path. It seems this is what Peter will have to do.

The line about mutation (and Peter's black eyes later in the trailer) leads some to believe that Peter may become Man Spider, a version of himself that is more spider than man. While I think this idea could be fun temporarily or in a dream sequence, I doubt that it would happen fully.
New Characters
The trailer is filled to the brim with characters from the comic which have fans jumping with joy. From The Punisher (Jon Bernthal) to Scorpion (Micheal Mando) to Tombstone (Marvin Jones III), the movie seems to be bringing back many characters from Spider-Man's rogues gallery.
Sadie Sink has also been cast to play an unknown role, and given that the trailer shows an unknown villain using mind control, many fans believe that she will be playing Jean Grey. However, I find this a little unlikely considering that the X-Men (which Jean Grey is traditionally a member of) do not currently exist in the same universe as the main MCU.

I worry that the film may be trying to juggle too many villains at once. Sure, Spider-Man is known for fighting the Sinister Six, but only one of these characters (Scorpion) is traditionally a member. The trailer doesn't seem to hint how they might be connected, only that they will be in the film.

Still, trailers don't reveal everything, the idea that this film will be overbloated is just speculation. Hopefully it will be spectacular!