The original book is magnificent. I liked the film... but it isn't.
Interestingly, for once a film adaptation has made the main characters nastier and less sympathetic. The book's Angier and Borden are tied into a rivalry in which people get hurt, but don't come near to playing the trick that's done here. The structure and ending's very different too.
L's comment was that the film presents the same central magic tricks, both men's versions of the Transported Man, but with a different image. What else to expect from a film from a book about illusion and the efforts needed to sustain them?
Having read the book helped because you can happily look for the clues to the two central secrets - I was amused to see various explanations going on in the audience when it finished.
I'm not sure how much they liked it. It certainly engages the brain, which can only be a good thing, but I'd have stayed truer to the original.
For those who've seen it without having read the book - when did you get the two secrets?
Apparently the largest grossing Asian film ever, this is a South Korean 'creature feature'. It breaks several rules, like showing the monster really early on, and has a nice political edge - the American dumping of formaldehyde into the Han river over Korean objections is true, and the one family which is particularly affected by the resulting (fictional) creature is given a hard time by the government.
The version at Frightfest was apparently the longest one and was, to be honest, a bit too long. I'd be interested to see what was lost, but seeing it once is really enough for me. Don't let that stop you if it's a genre you like: again, there's intelligence in the script here missing from most Hollywood monster films, and it's not afraid to avoid a happy ending for the innocent.