Blond Annabeth

Hi all:
Bombshell!! Alexandra Daddario's hair: from brunette to blonde. The original Annabeth Rick Riordan's novel was blonde, but the filming of "Percy Jackson and the Lightning Thief" was shot with a brown Annabeth Chase. In several images, is the shoot in which the actress appears with blond hair. This causes more intrigue to the movie. What will seem to change hair Percy? What excuse will the movie?
This time I would like you should say what you think and your opinions on the subject :D