The NeverEnding Story follows the journey of Bastian Balthazar Bux as he reads a book, The NeverEnding Story, about a world, Fantastica, that is dying. He travels along with Atreyu in his search for the one thing that can cure the illness that the Childlike Empress is suffering from. Atreyu's search eventually leads him to the discovery that only a human child can save the Empress and Fantastica from the Nothing. This is where Bastian comes in. Once he enters Fantastica and gives the Childlike Empress her cure, things change.
This is where the movie version ends. However, the story most definitely continues. While Bastian is plummeted into Fantastica, he becomes the Wisher of Wishes and can create and ask for anything he wants. The power that this gives Bastian soon causes him to commit some truly questionable things. In addition to the wishes, for every request he makes, a small portion of his human memory is wiped clean. Eventually Bastian has wished for so many increasingly extravagant things that he no longer remembers his human life. He has forgotten everything. And that presents a very big problem. Without his memories, how will he be able to get home?