Former Royal marine Commando and single mother Sam is brutally kidnapped on her way to the pharmacy. She wakes up disoriented in what seems to be a deserted military factory. Worried that she has left her baby alone at home, she hurries to find a way out but all exits have been sealed. She soon realises that she is not alone. Someone or something is preying on her. Stalked and attacked by an invisible foe, she must use all of her military skills and knowledge to survive this deadly game of cat...