It’s hard to pinpoint when Marvel trailers stopped being mere hype and started teeing up their own conspiracy theories, but it was probably around the time that early footage from Spider-Man: No Way Home appeared to show the Lizard getting thumped by thin air – and the internet correctly pointed out the recently deleted digital ghost of Andrew Garfield. Since then we’ve had Patrick Stewart’s voice hinting at a Professor X cameo in Doctor Strange in the Multiverse of Madness, and Wakanda Forever revealing a new Black Panther suit while declining to mention that Shuri was inside it.

Now it’s happening again with Spider-Man: Brand New Day. With the fourth Marvel Spidey film out next month, the internet is abuzz with predictions. “This movie is a real mystery,” Tom Holland told Esquire. “And for a large portion of the film even Spider-Man is a little bit at odds and lost and is like, ‘What is going on?’ We’re just trying to find ways to make this movie feel like a detective movie.”

So what do we think it’s all about? Two trailers have been released so far, revealing that Spider-Man undergoes some sort of weird metamorphosis, that someone or something appears to be playing musical chairs with human bodies, that the Hulk is back and bigger than ever, and that nobody knows Peter Parker is the wallcrawler due to Doctor Strange’s spell at the end of the last movie. Yet we’re no closer to actually working any of it out.

The problem is that, ever since three Spider-Men turned up in No Way Home, Marvel has trained us to treat trailers with a degree of healthy suspicion. If there’s even the merest glimpse of a shonky-looking frame, subtitle, eyeline or missing body, we’re on it. It doesn’t take much before even the flimsiest rumour is being upgraded to forensic evidence by bloggers and YouTubers. Take Sadie Sink, who has been cast in an unknown role. Some people think she’s playing the consciousness-swapping hooded villain from the trailers, a version of the X-Men’s Jean Grey who has been parachuted into a Spider-Man movie in the same way the webslinger once debuted in Captain America: Civil War. But others think she could be Parker’s daughter from another universe, the comic book favourite Mayday Parker, otherwise known (usually) as Spider-Girl. Or Rachel Summers, Jean Grey’s time-displaced daughter from the future. Or Madelyne Pryor, Jean Grey’s clone. Or Hope Summers, the mutant messiah. Or Shathra, a spider-wasp deity from the least user-friendly corner of Marvel continuity.

Then there is the Hulk. Mark Ruffalo’s Bruce Banner is involved in the trailers because it seems somebody wise and sciencey needs to explain to Parker why his eyes keep turning black and he’s shooting webs out of his wrists like it’s 2001 all over again. But the rumour mill, naturally, has gone further. Some fans think this is the long-awaited return of Savage Hulk, because the trailer also shows a bigger, angrier, less house-trained version of Banner than we’ve seen in years. Others appear convinced that Marvel has brought him in so that Spider-Man can fight one of the comics’ most famous heavyweights before discovering the real enemy – perhaps that body-hopping villain – is rattling around inside Hulk’s skull like a wasp in a pint glass.

Next up: Miles Morales, rumours of whose arrival in the Marvel Cinematic Universe appear to be based less on anything in the trailers than on the iron law that all modern movie Spider-Men must eventually multiply on screen like Gremlins caught in the rain. Let’s ignore for a moment the fact that Sony would be letting Marvel play with one of the cleanest bits of Spider-Man IP it still has largely to itself, namely Miles as the star of its own Oscar-winning animated universe. It would also require yet another desperate dip into the multiverse, just when Marvel had seemed to be trying to drag Spider-Man back down to street level.

Finally there are all the villain rumours. Tom Holland is on record saying that nobody has yet guessed who the real enemy is in Brand New Day. Which, given the number of people who have tried, seems less likely than the prospect of J Jonah Jameson opening a mindfulness retreat. Could it be Jean Grey? Mister Negative? The Jackal? Mister Sinister? Or perhaps William Metzger, the magnificently obscure anti-mutant zealot who would at least explain why this supposedly street-level Spider-Man film appears to be wearing X-Men pyjamas under its costume?

It’s likely that someone out there has already worked most of it out, just as they did for No Way Home. Unfortunately there are about 20,000 false rumours also out there, each one primed and ready to confuse everyone until opening night.