Tucked away in the English countryside lies the ominous manor of the Phantomhives, a family which has established itself as the cold and ruthless "Queen's Watchdog" as well as the head of London's criminal underground. After a tragedy leaves the Earl and his wife dead, many are shocked when their son, a young boy named Ciel, claims his place as the new Earl of the Phantomhive house. At first, many perceive him only as a child surrounded by a few eccentric servants. But they soon begin to realize that it is foolish to meddle with Ciel and his demonic butler Sebastian.

Taking place at the end of the 19th century, Kuroshitsuji follows these two as they face countless mysteries and dangers that plague England and threaten the Queen, uncovering the truth about what really happened to Ciel's parents in the process.