First, let me say that I am no expert in French animation, much less the works of Jean-François Laguionie, so I am reviewing this movie from the angle of the average film fan.
Gwen, the Book of the Sand, is a surreal journey in a would that appears created on the detritus of our own. In this world, the people eek out a living in a vast desert that they share with some birds and what appears to be the trash we'd find in any landfill -- old spectacles, rusty bikes, etc. Gwen, a newcomer to the tribe, forms a bond with a strange boy, who is soon taken by the mysterious entity that prowls the desert at night. Gwen journeys with the boy's grandmother into the unknown to find him.
The visuals are simple, yet serenely beautiful. The world is made strange by the juxtaposition of the desert nomadic motif to the common everyday items that, despite their normality, seem to physically dwarf the characters. Eventually, the movie begins delving into the question of religion and understanding the purpose and desire of "God." The pacing is necessarily slow to allow the journey. If you are the sort of person who likes clearly defined plots, this is not the movie for you, in that the world Laguioneie has created becomes confusing and undefined. However, fans of surreal animation will find this unique landscape something to think about.