The town of Willow Creek is like any other small, peaceful and beautiful town in America, where the people are kind and loving. However, behind the charm, there are strange and sinister things lurking, slowly growing and thriving. It seems like no one notices that the phone lines are being cut off and the wealthiest man in town, Grant (played by Michael Rooker), starts displaying odd behavior.
But when the farm animals are mysteriously mutilated and young women start disappearing, Sheriff Bill Pardee (played by Nathan Fillion) and his team must work together to uncover the truth of what is haunting their once peaceful town. With the help of Starla (played by Elizabeth Banks), Grant's wife, they must face the terrifying extraterrestrial creature that seeks to devour all life on Earth.