Plot

Ciel investigates a prestigious school where pupils, including royalty, go missing. He enrolls undercover while Sebastian joins as a housemaster to uncover the sinister truth.

Being the most esteemed public school in Britain, Weston College is so exclusive that it won't even accept help from the government. So, when several of the pupils at the school-including Derrick Arden, the cousin of Queen Victoria's son-refuse to return home and stop communicating with their families, Ciel Phantomhive is forced to enroll in Weston College in order to look into the matter. As Sapphire Owl's new housemaster, Sebastian Michaelis has joined the team.—Bilibili TV

Butler Sebastian Michaelis works with his 13-year-old master, the Earl Ciel Phantomhive, to do the dirty work of "the Queen's Watchdog" in nineteenth century England's gritty underworld. One day, Ciel receives a letter from Queen Victoria telling him that several students at Weston College, one of England's top public schools, have seemingly disappeared... including a relative of hers named Derrick. And so, Sebastian and Ciel infiltrate Weston College to get to the bottom of the matter. What truly happened to these students?—Kuroshitsuji Wiki

At the request of Queen Victoria, Earl Ciel Phantomhive goes to Weston College-a prestigious public academy for boys, known for its traditions and outstanding curriculum-to search for a relative of hers who has not returned home in months. Thanks to his noble status, the 13-year-old Ciel is swiftly able to enroll as a student, while his devilish butler Sebastian Michaelis assumes a teaching position at the school. Ciel does not anticipate being unable to locate the Queen's relative on campus. To make matters worse, he cannot request a meeting with the headmaster of the college, who may be the only person that knows anything pertaining to the disappearance. The only ones in frequent contact with the headmaster are the heads of the college dormitories, known as the Prefect 4 (P4): Edgar Redmond, Lawrence Bluewer, Herman Greenhill, and Gregory Violet. Ciel must concoct a plan to get in the P4's good graces if he wants to use their connections to succeed in his mission. But the distinguished college and its students hide much that is unseen, making this task more improbable than he could imagine.

The son of Queen Victoria's cousin is refusing to write or return home. To find out what caused this sudden change in behavior in Derrick Arden, Ciel enrolls in Weston College, the United Kingdom's most prestigious public school and a school full of ghastly secrets.