10 Shocking (But Believable) Spider-Man: Homecoming Theories
5. Another Hero (Specifically, Nightwatch) Could Appear
The Theory
Bleeding Cool have recently revealed that Sony employees have suspiciously begun taking a huge interest in Nightwatch, “buying up any and all comic books that feature the character.”
That could be entirely innocuous, but in the past that sort of behaviour has “usually indicated that a character is planned for an upcoming movie and all the employees want to know everything they can about them, ahead of meetings, discussions, plans and merchandising strategies.”
In other words, he's coming, it just isn't clear when. But, if Nightwatch were to be introduced, it's hard to imagine he'd be a stand-alone character (unless Sony are being far bolder than anyone could have expected) - he's probably more likely to be a side element in something like Sinister Six or the mooted female ensemble Sony wanted to make. And dropping him into Homecoming for a cameo (like Azrael appearing to Batman sporadically) might be the best way to seed that.
Why It's Believable
Because of what we know about the story predominantly: so far it seems Peter Parker will be caught in a balancing act between being a kid at school and being a superhero, and he needs an anchor on both sides of the split to offer him a picture of what he could become either way. On the one hand his friends at school living their lives will be the draw (with any negatives bundled in), and while he has Tony Stark, he's going to be more of a mentor, rather than an example of being a balls-out hero (he'd never allow him to leave school anyway.
So, in other words, he needs an extreme, and Nightwatch would fit that bill: his backstory saw him make the choice between normal life and superheroics (despite "knowing" it would kill him thanks to a time travel incident). It's a little bold (and a lot difficult to balance), but it's a smart story-telling device if they could get it right. And then they can spin him off.