A small town is suddenly and inexplicably sealed off from the rest of the world by an enormous transparent dome. While military forces, the government and the media positioned outside of this surrounding barrier attempt to break it down, a small group of people inside attempt to figure out what the dome is, where it came from, and when (and if) it will go away.

An invisible and mysterious force field descends upon the small town of Chester's Mill, Maine, USA, trapping residents inside, cut off from the rest of civilization. The trapped townspeople must discover the secrets and purpose of the "dome" or "sphere" and its origins, while coming to learn more than they ever knew about each other and animals too.

Phil Broker is a former DEA agent who has gone through a crisis after his action against a biker gang went horribly wrong and it cost the life of his boss' son. He is recently widowed and is left with a 9-years-old daughter,Maddy. He decides to quit the turbulent and demanding life of thrill for Maddy's sake and retires to a small town. His daughter fights off a boy who was bullying her at school and this sets in motion a round of events that end in his direct confrontation with the local Meth drug lord. His past history with the biker gang also enters the arena, making matters more complex. But he has a mission in his mind to protect his daughter and he is ready to pay any cost that it demands.

Capitol Policeman John Cale has just been denied his dream job with the Secret Service of protecting President James Sawyer. Not wanting to let down his little girl with the news, he takes her on a tour of the White House, when the complex is overtaken by a heavily armed paramilitary group. Now, with the nation's government falling into chaos and time running out, it's up to Cale to save the president, his daughter, and the country.