Ten - ten strangers are lured to an isolated island mansion off the Devon coast by a mysterious 'U. N. Owen'. Nine - at dinner a recorded message accuses each of them in turn of having a guilty secret, and by the end of the night one of the guests is dead. Eight - stranded by a violent storm, and haunted by a nursery rhyme counting down one by one, as one by one, they begin to die. Seven -which among them is the killer and will any of them survive?