A run-of-the-mill fantasy adventure.

The result is effective, if too intense for younger children.

The storytelling is economical and brisk. In some ways, Waters approaches it more as a pre-teen horror movie.

Highmore does well playing twins (though one admittedly doesn't do much) but it's the improvements on Mallory's character from the books, Bolger's realistic fencing technique, and the surprisingly fun (albeit not realistic) CGI that work best