If I were to view The Prestige with an ideological perspective, then I would probably try to look at the similarities and differences between magic and cinema. To do this, I would consider The Apparatus theory or perhaps any theory having to do with spectatorship.
As we discussed in class, the viewer of the film is most closely related to the audience of a magic show. This is done through camera placement, but also through the narration at the beginning and the end of the movie. At the end, Cutter addresses a viewer of a magic trick as well as the viewers of the film, saying, “Now you're looking for the secret. But you won't find it because of course, you're not really looking. You don't really want to work it out. You want to be fooled.”
Magic and film are similar in one huge way. The viewer suspends their disbelief in order to be entertained by the show. We try to forget the fact that the illusions we are seeing are not real. However, in movies we are only willing to suspend our disbelief so far. If the effects are bad or the story is implausible, we cannot enjoy a movie as much because we cannot forget the fact that a movie is all it is. So where magicians are never supposed to reveal their secret and try to maintain the illusionistic quality, filmmakers often must wrap up their film in a way that makes sense and is pleasing to an audience.
I feel like the reason we demand explanations at the end of movies, especially today, is because we know what film as a medium is capable. We know that through the use of editing, both traditional and digital, the image can be altered significantly, and we want the plot to be able to account for it. It is not enough to make something that wows and entertains the audience; film must also provide us with a plausible explanation within the narrative to give the experience some meaning, some relevance.