Writing movies is hard. We're guessing it is, anyway, because there seems to be a lot that can go wrong. For instance, occasionally in a movie the characters will wind up in a jam where they can be rescued only by some new science, device or technology. Then, once they're out of trouble, the tech is usually immediately forgotten.
The problem is, sometimes the device or technology itself should have been far more important than what the heroes were trying to accomplish in the movie. Consider ...
Spider-Man Has Gene-Splicing Spiders
Before teenager Peter Parker becomes Spider-Man, his class goes on a field trip to a genetics laboratory. A tour guide explains that they've genetically engineered 15 superpowered spiders. When one gets out and bites Peter, the venom rewrites his DNA to give him all sorts of weird spiderlike abilities. He stoically accepts the ramifications of being part-spider for the rest of his life.
"I have seen my future, and it involves a pian- oh what the fuck, Sam?"
Hang on a second ...
Uh, Peter, you don't think somebody needs to know about the spiders? You know, the fact that scientists have accidentally created something that can completely and irreversibly rewrite DNA with one bite? That would make them pretty much the most dangerous creatures on the planet. Think about it: At best, the results are unpredictable -- who's to say the next victim won't just turn into a deformed horror instead, or die -- but at worst, the bite victims will gain superpowers and maybe also become deranged or violent. These spiders could easily transform any person into a weapon of mass destruction.
Who wouldn't let this thing bite them?
And clearly the scientists didn't know the spiders could do it -- when Mary Jane pointed out that one had escaped, the lab didn't exactly go into lockdown.
No, only Peter knows, and he doesn't bother to tell anyone. And it's not out of ignorance; it's clear that Peter is some kind of science prodigy, so when he suddenly develops spider-powers immediately after being bitten by a genetically altered spider, it's unlikely he chalks it up to coincidence. It's not like he just developed a rash; a single spider bite rewired his genome. Yet the rest of the film is devoted to Peter's efforts to impress a girl.