Jack Harper has problems. His wife has run off leaving him to bring his young boy on his own, his veterinary business is ailing, and he's drinking. A lot. But things are about to get much worse for the village vet. When Jack finds some of the local livestock savaged, he suspects that there might be something prowling the countryside. Something deadly. He's not the only one who knows about the beast on the moor. Jack's son Tommy has become obsessed with the creature and will do anything to protect it, and Jack finds he not only has to hunt down and kill the night prowler, but has to face an even bigger challenge - to win over his son.