在这部亲密伙伴家庭/剧情片中,戴维的双亲不幸遇车祸身亡，他只好同他未曾见过面的外祖父亚当·麦克达姆一起生活。亚当性格孤僻，陪伴他的似乎只有酒和他的爱犬“扎克”。不久，戴维结识了另一只狗“老鲍勃”和小主人玛琪，并因此了解到了狗主人之间一段不愉快地过去。岛上出现了牧羊犬咬死羊的连环事故，究竟那一只爱犬会被“正法”呢……
Recently orphaned in America, teenager David Roberts must spend the summer with grumpy maternal grandfather Adam MacAdam, whom he never met, on his sheep-farm on the Isle of Man. Both long for the end of the summer, having nothing in common but their love for dogs, notably Adam's precious champion sheepdog Bob. David strikes a friendship with Maggie, the sassy daughter of friendly neighbor Keith Moore, but Adam hates that family on account of an old canine competition-related tragedy. Other neighbors suspect Bob and the Moore's dog of the recent series of nocturnal sheep-kills.
