Alex spends the majority of the movie dazed and expressionless. He is haunted by what happened but is also afraid. The police are investigating the death and think it might have been a murder. They are interviewing all the skateboarders at his high school since the murder happened near Paranoid Park, the local underground skatepark.
The story does not go in order and flashbacks of the event are gruesome. There is also a second telling of the same scenes from a different angle. This puts them in context but only happens halfway through the film once the accident has been revealed. It can be confusing and distracting, and if I hadn't read the description I would not have known what was happening in the first part of the film.
The acting is hit or miss. Once I got used to Alex's delivery, it worked within the context of the story. However Alex's friend Macy is stilted, unnatural, and sounds like she is in a high school play.