A film adaptation of a Manga cartoon by Takashi Murakami of Osaka (not the contemporary artist from Tokyo). An abandoned car is discovered near a camping ground, and inside it is the body of an unidentified middle-aged man and a dog who seems to have died months later. This is the story of the life of the loving and faithful dog Happy and his owner (Toshiyuki Nishida). Told from the dog's point of view, it follows him from his puppyhood with a peaceful family, through life's changes, and to the long journey he finally makes with his owner, who he calls "father". A second story, "Himawarisou", continues the narrative, following the caseworker Okutsu Kyousuke (Tetsuji Tamayama). As he investigates the situation above, he remembers his late family and his own dog's unfailing loyalty.