So me and dh decided to watch watership down tonight after both being traumatised by it in our childhoods (along with most of our friends).
The box describes it as "a delightful film for all ages" and states that it contains "mild threat and violence".
I'll quote from IMDB who sums it up quite well.
It lists several examples of violence/gore - the worst being "In the final battle, which is likely the goriest scene in the movie, a rabbit has his throat torn out by another rabbit onscreen. We then see his body, he has a large hole in his neck, and blood is everywhere. Two rabbits then fight nearly to the death. They cut each other up, and are shown bloodied. Next, a dog is unleashed upon the rabbits, he bites and tears up many of them. One is even shown being thrown high into the air by the dog, and falling back down, covered in blood. Finally, it is implied that a rabbit is killed offscreen by the dog, no blood or violence but still very frightening."
ON frightening intense scenes it describes how "The most frightening scene shows rabbits being gassed underground, their heads then form an abstract ghostly head of a rabbit." but misses out how the rabbit describes the piling up of dead bodies and the others trying to climb over them to get out their warren which has been blocked up.
Oh and also the weird warren run by a mad dictator (General Woundwort).
For those of you who don't know the story it is about a young rabbit who has visions that terrible things are going to happen (he continues to have these throughout the film). He convinces a group of rabbits to leave the warren with him and they go off to search for a new home making their way through constant terror and danger.
It's supposed to be a religious allegory btw and is based on the book by Richard Adams (a very good book btw).
But aibu in thinking that this film should definately not be rated as a U?