A brief note on spoilers in reviews and blogs: I want to review this film/book and explain just what works. The plot is so tightly coiled however that almost anything I put into it will be a spoiler. The setting is not typical science-fiction, rather the conjuring-inspired novel which is becoming a genre of its own (Carter Beats The Devil, The Bullet Trick etc.) Here two playhouse magicians carry out a lifelong and deadly rivalry over the secret behind a certain illusion. However the central theme is one of the major science fiction concepts, associated with paradoxes and solutions in the literature, as well as speculation in real-world science. It isn't time travel or aliens - it's one of the other major concepts.
This is the main area where the film scores higher than the book - the scenario in the book, horrific though it is, skirts around the paradox. The film tackles it head on, and by showing you at the start the surprising (and gory) secret behind a particular magic trick, makes the paradox totally accessible and proves that it pre-dates science fiction! That's all I'm saying. I'd like to write a piece about this particular concept and how it's used in science fiction in general - and I will - but when I do I won't be able to mention the Prestige.
The book and film share a complex plot, both using structure (the book uses viewpoints from two journals, the film uses a non-linear flashback-heavy narrative) to tell the story unravelling the twists in an appropriate order. The result is gripping.
Something that works perfectly in the book and film is the inclusion of legendary physicist Nikola Tesla in a key role. Portraying Tesla essentially as a true worker of magic is romantic but more or less accurate - it just so happens that the mysterious Force he learnt to manipulate was the alternating current; his discoveries and demonstrations would have been indistinguishable from magic at the time to anyone but himself. At the end of his life he was penniless, quite possibly insane, and pursuing a range of concepts including the one in the film, as well as energy weapons and anti-gravity. There's no way of knowing whether he was delusional or onto something and might actually have achieved some of those things. Oh yeah, and whoever thought of casting David Bowie as Tesla was spot on and gets the sci-fi gene seal of approval.