It could be a thriller. If it's about a true - life crime or a dangerous situation, the elements of suspense and danger would fit well into the thriller genre.
Another possibility is that it could be a documentary. If the main purpose is to present the true story as it happened, without much fictionalization, then it could be a documentary. This would be especially true if it aims to inform the audience about a particular event or situation that was savage in nature, like a war or a natural disaster.
It could be a thriller. If there were some dangerous or mysterious events that happened in the ravine in real life, it would make for a great thriller plot.
It could be a drama. Since it's based on a true story about the afflicted, it's likely to involve a lot of emotional and complex human situations which are typical of the drama genre.
It could be a drama. Since it's based on a true story about a boy, it might deal with real - life emotions and situations that are often found in dramas, like family relationships or personal growth.
It might be a drama genre. Given that it's based on a true story, it could be about the emotional and interpersonal relationships of the twelve people. For example, if it's about twelve family members dealing with a family - related real - life issue, it would be a drama.
It could be a thriller. Since it's based on a true story, there might be elements of real - life danger and suspense that would fit well in the thriller genre.
Maybe it's a documentary - style work. Since it's based on a true story, it might present facts about Nathan's life in a non - fictional way, similar to how documentaries are made. It could include interviews, real - life footage if available, and a narration of his story.
It could be a horror genre. Since it involves the concept of being 'possessed', which is often associated with scary and disturbing elements like the loss of control over one's self, and the presence of some unknown and potentially malevolent force. This is a common theme in horror works.
It could be a thriller. True stories often have elements of mystery and danger, and when a stranger is involved, it can add to the suspense. For example, if the stranger is linked to a crime or some sort of secret.
It could be a thriller if the 'swarm' represents something menacing like a swarm of locusts or a group of criminals.
Maybe it's a documentary - style work. Given that it's based on a true story, it could present the facts about the undershepherd in a more factual and educational way, much like a documentary would do.