Moderate. In a Quidditch match, lightning strikes a chaser's broomstick making him fall down.
In a boggart defense lesson, a girl has a snake for a boggart and changes it to a jack-in-the-box clown leaning forwards and backwards moving his hands like they're going to push you. It's very frightening to viewers who are afraid of clowns when it leans forward to the screen.
This movie is a bit scarier than the previous ones but still not that scary.
The scene where Harry Potter blows up his Aunt Marge could be considered frightening to some, but most would probably consider it hilarious.
The first appearance of a Dementor happens on Hogwarts Express. Everything goes dark and windows freeze, then suddenly a large, rotten hand appears on the door of the carriage. Pretty dark and unsettling scene.
The images of the werewolf can be quite frightening to some.
There is a scene where Harry is playing Quidditch (wizard sport on broomsticks) and dementors show up during the match. It is high up in the clouds during a thunder and lightning storm. A dementor rises up right in front of the camera and we see inside it's decayed mouth. A shocking and unpleasant jump scare.
Film takes a tone shift that will be started with the 4th film. While this movie is PG, it's still very scary in some scenes
This film is more darker than the first 2 movies
This film has a much darker tone and atmosphere than the first 2 films, because this movie is the point in the series where it starts to shift from being kids movies to a dark and sometimes depressing series of films despite this one and the later ones still having light and humorous moments.
This film is quite dark, thematically and visually, but not too frightening. Children should be able to handle it.
The plot of the film revolves around a convicted murderer escaping from prison and going after Harry, supposedly to kill him.
All scenes with Dementors are quite frightening and intense. The purpose of a Dementor is to suck out all of your happiness and only leave you with your own misery. Various characters (prominently Harry) encounter Dementors a few times throughout. The appearance of the Dementors can be frightening.
Lupin's transformation into a werewolf is particularly frightening. You see his backbone protrude and reshape as well as his feet and his face. He then goes on to attack Harry, Ron & Hermione but is intercepted by Sirius (as a dog). They erupt into a fight and Lupin nearly kills Sirius.
In one scene, Sirius and Harry are attacked by about 100 Dementors at once. Multiple Dementors try to suck out their souls and both of them are nearly killed, but they are saved at the last second. While the Dementors are not violent, it is their appearance and what they can do such as sucking out a person's soul which makes them frightening. Overall, an intense scene.