A boy named Hansel and his sister named Gretel along with their friend Jack...
This is the intro scene where a picture of the cityscape can be seen. It is to set the setting and mood of the story.
Continuation of the cityscape scene where a text box is also included that say 'Once upon a time' making it seem like it is a modern fairy tale mashup.
Introduction of character, we can see Hansel, Gretel, and their friend Jack standing in front of a building that is meant to be the orphanage. In conclusion, Hansel, Gretel, and Jack are orphans in the modern world.
In this scene it shows a beach where Hansel, Gretel and Jack are off to fetch a pail of water from the ocean near the beach. From the scene here, Jack can be seen smirking like he is planning something mischievous while Hansel and Gretel were unsure
Were on their way to fetch a pail of water
This scene is to raise tension as the audience wouldn't really know what happened because no characters are on screen and there are exaggerated words saying splash. With this the audience must have already known the event is related to water.
When all of a sudden...
This scene shows what happens after the tension in the scene before, which is a scene where Jack fell in the water because he was joking around near the edge of the water. This scene also shows how helpless Hansel and Gretel are with their drowning friend. This scene should also show that Jack can't swim and in the end he drowned.