In this game you control Miette, an orphan girl forced to steal by the director of the orphanage where she lives, in a gloomy city where children are captured by mysterious individuals. During her thefts, Miette meets One, a man whose little brother was kidnapped, who involves her in a much more important mission: to find out where the children have been taken and save them. The story of the game loosely follows the plot of the movie from which it was based. If at some points you don't know how to proceed or you cannot understand the plot of the game, it is definitely a good idea to see the movie first, which can be of great help to you.
In the role of Miette, you must therefore explore this tangled mysterious city, fulfilling the tasks assigned to you. You will have to talk to the people you meet, some of whom will be willing to help you or give you useful information, while others will try to hinder you instead. Miette can interact with the environment that surrounds her, for example by pressing a switch or opening a door, by pressing 
. If she Miette can't do anything where she is, she will tell you. You have to scour all the environments, solving puzzles and searching for useful items to proceed. Usually, these items aren't immediately visible. When you get close to an item that you can pick up, it appears in a large window on the left of the screen. At this point, you have the option to pick up this item, to do so just press 
. After picking up the item, Miette will hold it in her hand. The item she is holding is shown in a small window on the right of the screen (note: you cannot hold more than one item at the same time). By pressing 
, Miette will place it in the inventory. Miette can carry a maximum of 10 items with her. Similarly, if you want to drop an item that you no longer need, you can press to access your inventory, and select an item to take it by pressing . Pressing again Miette will drop it on the ground. Almost all items in the game have their uses, so be careful not to abandon items that you may still need. Sometimes then, to perform a certain action, it is necessary to have a certain item in hand (for example to open a locked door with a key). To do so, take the item from the inventory as described above, go to the point where to perform the action and press to proceed. Similarly, sometimes it may be necessary to give an item to a character. After taking it from the inventory, go close to the character and press to give him the item.
In some moments there are animated sequences that explain the evolution of the plot and that you can skip by pressing .