When a hopeless stag party goes on a mock zombie survival weekend, an unfortunate turn of events leave them fighting for their lives.

A battle-scarred War on Terror bounty hunter is forced to go to London on a manhunt for a disavowed CIA operative, which leads him into a deadly running battle with a former military comrade and his private army.

The real "battle" is the insurgence within mankind itself.

Two shocking and unexpected murders shatter an already fractured community leading to one of the largest manhunts in British history.