Stanley was a man suffering from the loss of his pregnant wife. He choose drinking as a solution to forgetting his pain. Tired of dealing with him and his drunkenness, his sister Tammy forces him to seek help from a doctor. When he first meets the doctor, Stanley is aware that something is not right with the man. How he smiles, the way he stands, even the way he talks makes Stanley afraid of him. Going along with his sister's advice, he agrees to see the doctor for help with his problem. Soon as he arrives for the first day of treatment, he's drugged by a nurse then escorted onto a bus by male workers. They transport him and other patients to an unknown building where they are secretly implanting black, snake like creatures into peoples' heads. Being freed by one of the patients who knows about the secret operation going on, they both escape the building and try to figure everything out. They seek help from friends who join them in exposing the aliens' plan. Trying not to get caught, they make their way back to Stanley's house after burning down the building. They later find a weakness they can use against the creatures to kill them. They test the theory on Stanley's neighbor, who has a creature in his head, and finds out he was a big part in what was going on. Not only that, he has information about queens in a secret location. They decide to go to the location to kill the queens and see what else they can find. Things look to be going their way when the army gets ready to join in and start flushing the creatures towards the North East so they can freeze to death. Stanley and the others are sent back home to wait for further instructions. Feeling better about himself, Stanley no longer wishes to drink and has to figure out how to move on after what he's been through.