What’s interesting here that no Kubrick aficionados ever pick up on is that Charles Grady exists only in the movie – not in the novel. It's only Delbert Grady who exists in the novel. He’s both the “caretaker” who kills his family and the ghost who lets Jack out of the larder and puts the roque mallet in front of him to kill his family with. In the movie Delbert Grady and Charles Grady are two different entities and Stanley Kubrick is very precise as he comments about Grady. What he's talking about is obvious yet many totally misread this quote from his interview with Michel Ciment and try to use it as proof that Grady, a real ghost, let Jack out of the storeroom. Note this, if you read closely you’ll see Stanley Kubrick is talking about what happened in the novel and not the movie. "…What I found so particularly clever about the [way the novel was written]. As the supernatural events occurred you searched for an explanation, and the most likely one seemed to be that the strange things that were happening would finally be explained as the products of Jack's imagination. It's not until Grady, the ghost of the former caretaker who axed to death his family, slides open the bolt of the larder door, allowing Jack to escape, that you are left with no other explanation but the supernatural."
He cleverly keeps his secret as he tells Michel Ciment exactly what everyone expects to hear; a ghost lets Jack out of the storeroom. But he's talking about the novel and this can't be ignored. If you read the novel (click here) there's undeniable proof that in the movie Stanley Kubrick has reversed or altered every major aspect of it, even Grady's name, and there’s no way to prove that he stopped doing it in the storeroom scene. Stanley Kubrick simply reverses what happens in the novel here and he cleverly hides what he's doing in the interview by talking about the novel and not the movie. “The strange things that were happening would finally be explained as the products of Jack's imagination” and that’s exactly what he did. In the novel there's no question that a ghost opens the door. In the movie the ghosts are all in Jack’s head mingled together with that very special hidden ability, "The Shine", that enables him to move things by telekinesis. Jack has the ability and opens the storeroom door himself, and he does.