Legend holds that when Britain is in its darkest hour, King Arthur will return to save the country, if not the world. The legend is dead wrong. When a grove of Druids sacrifice the lives of a group of innocent people, including the fiancée of a member of SEAL Team 666, the ancient king is brought back from the dead and sets his sights on subjugating humanity and cleansing his land of all who are not true Britons. Because of political sensitivities, Triple 6 is ordered to stand down, but that order is ignored by one of them seeking his own vengeance. Now, the members of America’s elite supernatural-hunting team must decide what is more important: their orders or their loyalty to a member of their team.