A young lord and his demon butler board a luxury cruise ship to investigate claims of the dead being returned to life, and are faced with various complications.
Whispers turn into screaming headlines in Earl Ciel Phantomhive's morning paper as word of the dead being resurrected takes society by storm. But when the unsavoury details of the business reach Ciel's ear, he and his superlative butler, Sebastian, book themselves on a luxury liner to look into these alleged miracles and the "Aurora Society" conducting them. As the waters lap and crash all around the vessel, mysterious individuals gather under the banner of the "Phoenix." Ciel and Sebastian may be one step closer to the truth, but have they sealed their fates by conducting an investigation on what could easily become a floating coffin...?—Alois Trancy
Ciel boarded the luxury passenger ship Campania, accompanied by his servants Sebastian and Snake. Tagging along with the Midford family, Earl Phantomhive was there to investigate a sinister case of illegal human experimentation, however. A shady doctor appeared to be the mastermind, as he demonstrated to the Aurora Society how he had been bringing the deceased back to life. The reanimated dead were not quite human however, as what was left of the people on board were about to find out.
In April 1889, Earl Ciel Phantomhive and his servants, Sebastian Michaelis and Snake, board the luxury passenger ship Campania alongside the Midford family--not for recreational purposes, however, but for investigating illegal human experimentation, which is later demonstrated at an Aurora Society meeting headed by a questionable doctor. Deceased individuals are coming back to life, but they have changed into something other than human. What is reviving the dead--a breakthrough in medicine or an unforeseen force?
The young Earl Ciel Phantomhive-the Queen's Guard Dog-is once again called to investigate seemingly supernatural phenomena when news of miraculous resurrections begins to surface in Victorian London. Along with Sebastian Michaelis, his demon butler, they board the luxury cruise liner Campania to investigate rumors of the Aurora Society-a medical organization suspected of experimenting on the dead. Grim reapers begin to appear on the ship, and it becomes apparent that the ship is about to be overrun with the undead as a devious plan is put into motion. Ciel and Sebastian must now uncover the secrets that lie behind the Aurora Society's phoenix symbol, and with the help of some old acquaintances, return the undead to their coffins or share a watery grave.
The story is based on the sinking of the Titanic in 1912. Ciel, Sebastian, and Snake board the luxury liner Campania on her maiden voyage to investigate the mysterious Aurora Society, rumored to perform unethical experiments to raise the dead. On board is also Elizabeth and her family. In a secret Aurora Society meeting, Ciel and Sebastian witness Doctor Rian Stoker use a machine to reanimate a dead woman, who starts attacking and killing the attendants. Ciel finds himself trapped in the ship's cargo with Elizabeth and Snake, where they realize that Stoker brought thousands more reanimated corpses on board. Sebastian rescues them. Upon interrogating Stoker, Ciel discovers that an even larger batch of corpses is stored in another area of the ship; that batch promptly awakens and begin killing the ship's crew and passengers. Amidst the chaos, the ship crashes into an iceberg and starts sinking, giving Sebastian and the Grim Reapers, including Grell, only a few hours.
The group discovers that Undertaker was behind the reanimated corpses and is a Grim Reaper himself. While fighting him, Sebastian is wounded by Undertaker's death scythe and his Cinematic Reel is played; Undertaker witnesses the early moments of Ciel and Sebastian's relationship, when Ciel summoned the demon, when they returned home, and Sebastian training Ciel for his royal duties until he re-entered society, receiving his title as Earl Phantomhive. Stoker falls to his death; Ciel is able to snatch Undertaker's funeral lockets as the Reaper escapes. Sebastian and Ciel barely escape the sunken ship on a lifeboat but find themselves surrounded by the remaining corpses. Knowing that the corpses will attack the other survivors should they attempt to escape, Sebastian has no choice but to fight all of them himself to protect Ciel. At dawn, with all corpses disposed of, a rescue boat appears to save them.
In the post-credits, William rescues Grell and Ronald, scolding them for failing in their task, while Sebastian and Ciel meet their friends aboard the rescue boat.
