In the indeterminate future, a new planet has just been colonised by humans just starting to reach out to the stars. The colonists included Colonel Cadmann Weyland as the "security expert" intended to keep everyone safe. Everything seems perfectly safe and predictable and the colonists begin to relax their security measures, prompting Weyland to become even more paranoid in response. Then cattle start showing up mutilated, and it seems that the colonists are not as alone as they thought...
With this story, its very simplicity is what wins over, is basically a re-run of "Jaws" with a twist as everyone blames Weyland for the problems which the reader knows full well are caused by something much nastier. Even so, the plot of this book can be summed up in a few words - which is why I wish oh wish it could be made into a movie.