Other reviewers have already mentioned what the story is about (at face value, at least): the rivalry of two Victorian stage magicians - Alfred Borden and Rupert Angier. They have also mentioned how Priest approaches his subject material: after a short introduction, centered on two modern-day descendants of Borden and Angier, the reader is presented with Borden's journal (and hence his version of the feud). After briefly returning to the present day, it's Angier's turn: the lengthiest part of the book deals with his take on events, as set out in his diary. Finally, it's back to the present for a short and sharp conclusion - with horrific overtones (think "Turn Of The Screw" here, not "Night Of The Living Dead").
What other reviewers have not really pointed out yet, however, is the following: the story doesn't make sense. Most importantly, there seems to be no real reason for the magician's feud. Okay, there're reasons it started - good ones, in fact - but no explanation is given as to why it continued (and, indeed, got quite out of hand). In fact, in their respective accounts, both magicians repeatedly mention wishing it to end.
So why didn't it?
Well, there would seem to be two explanations. Firstly, Priest may have purposefully left out essential ingredients in the two magicians' tales, leaving us to figure out their real motives for ourselves. If so, it might well be that "The Prestige" is not just a stylised (if somewhat stilted) exercise in pseudo Victorian romance, but also a well thought-out and intelligent story. In that case, though, I have to admit Priest has set me a challenge I could not meet. Simply put, I read a book I didn't understand.
The alternative is this: Priest, so taken up with the style and outline of his tale, has simply forgotten that his characters should not only act, but act believably. He's forgotten that every story, first and foremost, needs a credible plot (unless you're Virginia Woolf, of course, but that's another matter entirely). But if that is true, "The Prestige", for all its stylistic merits, is very fundamentally flawed indeed. It is, ultimately, a whallop of Victorian cream without a strawberry in sight.
I understand that this may seem to be a slightly abstract review. But think of it this way: to what extent are you prepared to be tricked by an author? Say you're reading a detective story, and at the end there's this great and unexpected denouement (no, she couldn't possibly be the murderer - oh, wait - yes of course! How clever!). And then, suddenly, the realisation that things don't add up at all (that's just stupid!). So: was it, after all, a good book or bad?
In the end, the question "The Prestige" raises goes to the heart of storytelling. Which is why it may be a great book - but probably isn't. And which is why, perhaps strangely, I'm giving it four stars. After all, it gets you thinking. And that can't be bad, surely...