This is volume two of the series. In volume one, the two young heroes of the story, twins Josh and Sophie, traveled to France and met the aged Nicholas Flamel and his wife Perenelle (who was imprisoned by the bad guys in volume one and spends this entire volume on Alcatraz). This volume continues from there and in it, delving quite deeply into Norse mythology. Sophie begins to learn the use of fire magic, and Josh seems to have no magical powers at all, which affects her character throughout the volume.
Why the one has power - and that particular power - and the other none isn't really explained - not that I recall, but it's been a while since I read this so my recollection may be faulty. Josh does get a nifty stone sword later -which has its own power - and the gift of military knowledge. You can call 'sexism' on the girl getting the magic and the boy the martial gifts if you like, and you can certainly call out Josh for being a little whiny bitch in this volume. There are ways to make him consider going over to the other side without making him quite so obnoxious, but I guess the author didn't know that.
There's a lot more action in this volume since all the set-up has been completed in volume 1, and a lot of new characters show up including some Valkyries who have a grudge against Scathaich. I commend this as a worthy read.
