I watched a film about 5 years ago when I was a teenager and I remember lots of details about it because this movie genuinely shook me because of some graphic scenes. Anyway I didn't finish watching the movie because of private reasons and I would like some help to find it.
The main character is a tanned male who is about 16 his age isn't really shown in the film we only know he is a small vulnerable child.
The movie is set in the UK I believe and the introduction is something like a dark Simpsons intro instead of Bart we see a crow flying around a suburban area and it then zooms into a high school.
We are introduced to 3 characters the main character and two other side characters. The two other side characters is a girl and a Chinese boy.
The next bit is a bit hazy for me but the school are planning a school trip to some factory up on a hillside.
Somewhere in-between the movie we see all the family members of the main character and he has a young sister a mother a father and a grandpa I believe he is an migrant because he has no other family members other than 1 cousin who lives a couple streets down from him.
Anyways, when the children arrive at the factory the teachers are told to go to another room and the children are all marched up some stairs, not sure where to.
This factory belongs to some organisation that test gases and other products on children to see how they react compared to older people and to see how their bodies function when going through puberty and stuff.
Not enthusiastic about this school trip he falls back and stumbles into a private room in that room he finds screens showing information about the city and the organisation and he soon discovers experimentation files and terrified he runs which sets off an alarm that alerts security and scares the main character.
He survives by hiding in different parts of the factory for like a week and I am not sure how he gets food or water
He eventually escapes but just before his complete escape he looks through a small window and he sees the two characters I talked about before (the girl and Chinese boy) hanging from some kind of meat hook all mutilated and bloody, their face looked like it has a tumor on it and pretty much that's the most scariest scene for me.
Anyway he eventually found out the exit through a small gutter or something and he found out that all the parents of these children are on some software and it instructed soldiers to go to their house and like use some amnesia potion to make them forget about their children like the men in black weapon; but more potent.
The kids are also wiped from all software's and no proof is there of them ever existing.
Anyway he is constantly followed by black vans trying to kidnap him because the factory owner finds him with some satellite
He runs to his grandpas house and for some reason he remembers him and it turns out he used to work for their organisation and they do some Star Wars thing and blow up the factory as if it was a Death Star.
The film is very gruesome and pretty much all the main characters die except of course the protagonist.