In Victorian-era Long lives the young boy, Ciel Phantomhive. On the night of his tenth birthday, a fire engulfed his manor, his parents were murdered, and he was captured by cultists. After a month of enduring excruciating and humiliating torture, Ciel returns to the Phantomhive household with an enigmatic black-clad butler, Sebastian Michaelis. To others, it seems that the butler is simply the best at his craft, from anticipating his young master's needs to carrying them out to the best of his inexplicable abilities.

Little do they know, Sebastian is actually a demon that has entered into a contract with Ciel, promising to help the boy achieve revenge on those who have wronged him in exchange for his soul. As the Queen's guard dog and standing at the top of the British underworld, Ciel solves the crimes plaguing London while waiting for the day he will exact his revenge.