The movie seemed to follow the book fairly closely. If you have not read the books I think you would be lost. We felt Jace and Valentine were miscast but they hit the nail on the head with the rest. Lilly Collins was perfect as Clary. Every setting/scene really was almost exactly what I imagined from reading the books. Our theater was empty, if that is any indication. Not sure if it is because people just do not know about these books? Or the bad reviews scared them off? All in all we didn't love it but didn't hate it either.
Pros great story
Cons too complex, if you didn't read the books you might be lost