For all that it is a complex and extremely clever piece of film-making.
According to Josh Larsen (Larsen on Film) "One of the movie's startling characteristics is the way it refuses to anthropomorphize its canine characters. Hagen (the dog at the centre of the story) has personality, but no more than any dog does. His behaviour is never out of character for his species. The same goes for everyone in the animal cast. This lends the movie’s showcase scenes – of up to 250 dogs racing in a pack down the abandoned streets of Budapest – a sense of fearsome wonder.”
The canine actors playing Hagen – two dogs called Body and Luke – put in a performance that is nothing less than extraordinary.
It's going to be a fascinating afternoon's viewing – and potentially a tough one for dog lovers. The reviewer from Arizona Republic seems to sum it up best:
Lassie it ain’t! What it all means is open to interpretation. Read it as a parable or as a horror movie. Read it as the story of love between a girl and her dog. Read it however you want. No matter what your take, you won't be disappointed.