On one hand, what better than animation to create an unusual and unique story like this. On the other hand, where did it come from? It's absurd, but in a way that's neither technically bad nor good.
It almost has a quality of a fable or a nighttime story a parent makes up for their child on the spot before bedtime. On one hand, that gives it refreshing freedom to do whatever it wants and go wherever it feels, but on the other hand, why? However, it's dry wit and loving appeal make it very entertaining and worth the watch, and for a rough and simplistic style of animation it does create some very interesting lighting techniques. It seems like a really, really good animation some kid did in his notebook at school, so if that appeals to you then by all means see it. It's just kind of odd.
Oh, and Giamatti's narration is great.
--PolarisDiB