The world is in the midst of the industrial revolution when hideous monsters arise from a mystery virus, tearing through human flesh to satisfy their insatiable need. The only method to kill these "Kabane" entities is to shatter their steel-coated hearts. However, if one of these creatures bites the victim, the person is destined to a destiny worse than death, since the fallen rise once more to join the ranks of the undead. Only the strongest fortified civilizations have survived this upheaval, like on the island of Hinomoto, where mankind has built a great wall to shield themselves from the unending hordes of Kabane. The only route inside these massive strongholds is by heavily armored trains.