Yuukoku no Moriarty

William Moriarty investigates nobleman Lord Argleton for murdering seven boys in late 19th century London.

William James Moriarty, residing in late 19th century London, investigates a serial killer who murdered seven young boys. He deduces the perpetrator is a nobleman who met the victims at their fathers' shops, except for one homeless boy. After interviewing the homeless boy's friend, William determines the killer observed the victim from the Gastros fine dining club. His brother Albert secures entry, where William suspects founding member Lord Argleton due to clothing purchased from the victims' fathers. William hints at his knowledge of Argleton's obsession, prompting a thug attack that Louis easily defeats. William then hands the restrained Argleton to a grieving father for revenge. This reveals William secretly operates as a crime consultant with brothers Albert and Louis, helping clients commit crimes. With authorities unaware of Argleton's fate, William considers it another perfect crime.

The Scarlet Eyes Act 1

Albert adopts fake William and Louis, leading to the real William's death and a mansion explosion.

Days before the fire, Albert adopts fake William and Louis despite his mother's objections. His father further angers her by funding Louis' surgery to impress another woman. The real William tries to bully the brothers but fails. After hearing his family disparage commoners, Albert agrees with fake William's views on class and decides to assist him. That night, the real William attempts to frame fake William by hiding stolen silverware in his room. Fake William anticipates this, catches him, and allows Albert to stab the real William as proof of loyalty. Albert then poses the real William in bed to simulate death and triggers a gas explosion that kills the real William and Albert's parents. As the new Moriarty head, Albert tells authorities that fake William is the true heir and Louis is their adopted brother.

A Rare Breed

William investigates Lucian's disappearance and Dudley's scheme involving Frida's death.

William discovers his student Lucian Atwood is missing after dating commoner waitress Frida. Dudley Bale advises ignoring the matter, but William learns Lucian proposed marriage and Frida became pregnant. After a man claims Lucian abandoned her, Frida drowns on a bridge. Dudley staged this as suicide while imprisoning Lucian in a brothel. William enlists Sebastian Moran and Fred Porlock. Fred rescues Lucian and positions him near the bridge. Dudley arrives to retrieve Lucian, but Frida emerges from the water, terrifying Dudley into confessing to drugging her. William reveals Frida is Fred in disguise. He exposes Dudley’s network of brothels and opium dens used to blackmail noble families. Sebastian shoots near Dudley’s feet, causing him to fall into the river and drown. Lucian has Frida buried in a noble cemetery.

Count Blitz Enders is framed for murder as William executes his societal reform plan.

A commoner is hunted and killed by dogs, setting the stage for the Noahtic maiden voyage. Onboard, the arrogant Count Blitz Enders criticizes the presence of commoners. William has previously outlined a scheme to transform London through crime, using murders to expose noble abuse, starting with Blitz. Sebastien pays Thomas Michaelson, a violent criminal, to provoke Blitz, anticipating that Blitz’s reaction will justify his elimination. Fred escalates the tension by sending a telegram falsely claiming Blitz’s home burned and a mine closed. William also demonstrates his mathematical deduction skills to an unidentified man. Blitz, revealed to be a hunter who kills commoners for sport, lures and murders Thomas in his cabin. William then enters the cabin to frame Blitz for the crime, advancing his plan to educate the public on aristocratic corruption.

Moriarty and Blitz stage Thomas's death while William confronts Sherlock Holmes about the deception.

Moriarty agrees to cover up Blitz’s claim that he killed Thomas in self-defense, and they throw the body into the sea, though Fred and Sebastien secretly recover it. During a ballet, William reveals to Blitz that Thomas is alive. Blitz chases Fred, disguised as Thomas, intending to kill him again, but instead finds the actual corpse. As Blitz stabs the body to ensure death, he is publicly exposed as a murderer and disarmed by a man who suspects the corpse is fake. Blitz climbs the mast to escape, but Sebastien shoots him with a silenced rifle, causing him to fall to his death. William plans to have Parliament investigate Blitz’s hunting grounds to incite public outrage when the bodies are found. He also expresses concern to his friends about the man who deduced the murder was staged, who introduced himself as Sherlock Holmes.

Holmes and Watson investigate a murder while dealing with rent issues and police suspicion.

Sherlock Holmes faces eviction from Mrs. Hudson due to unpaid rent. Dr. Stamford introduces Dr. John Watson as a potential flatmate, a retired army doctor whom Holmes identifies through deduction. Mrs. Hudson approves Watson’s move-in. Inspector Lestrade arrests Holmes for the murder of Count Drebber, who wrote Holmes’ name in blood before dying. Assistant Inspector Gregson gathers evidence despite Holmes’ claims of forgery. Lestrade allows Holmes and Watson to examine the crime scene. Holmes secretly takes evidence and, with Watson, proves Drebber died too quickly to write his name and that the writing belonged to a large, unskilled shooter controlled by a mastermind. Holmes recognizes the work of the Moriarty organization. Excited by the challenge, Holmes passes a note to Watson. William orchestrated the murder to help a terminally ill man seek revenge while testing Holmes’ deductive skills.

Holmes deduces the killer's identity while William observes his methods closely.

Holmes secures Lestrade's permission to escape by promising him credit for solving Drebber's murder. He shows Watson a stolen wedding ring engraved with Lucy, placing a newspaper ad to lure the culprit. William sends Fred disguised as an old woman to claim the ring, allowing him to escape. Inside a hansom cab, Holmes explains that Jefferson Hope, Lucy's husband, murdered Drebber after Drebber raped and bribed lower-class women. The Baker Street Irregulars located Hope based on Holmes' description. Hope, suffering from a terminal illness, offers a deal: if Holmes shoots him, Fred will reveal their master's identity. Holmes refuses, choosing to deduce the truth himself and handing Hope over to Lestrade. Witnessing this integrity, William decides Holmes is worthy of being his nemesis.

Holmes investigates a death in York while confronting the Moriarty brothers on a train

Holmes experiences a nightmare about killing Jefferson and confesses to Watson that he seeks greater challenges than the Drebber case. After firing a gun to alert Mrs. Hudson, Watson, and Lestrade, the trio travels to York to investigate the death of the Viscount of Redshire on a lakefront. Holmes and Watson argue following their inquiry. On a dining car, Holmes identifies William and Louis, accusing William of orchestrating aristocrat murders. William dismisses the claim as a bluff requiring proof. When Lestrade meets the Moriarty brothers, a corpse is discovered. Holmes proposes a contest to William to solve the case first, but Watson arrives covered in blood.

Holmes and William investigate a jeweler's murder while Mycroft seeks royal permission for secret documents.

Railway police detain Watson, who claims blood came from a stranger near the toilets. Holmes and William determine the victim, Trevor Redwood, was a jeweler accidentally killed during a robbery after being drugged. Holmes follows physical clues while William profiles the killer psychologically. Both conclude the culprit is a porter unable to discard a bloody uniform. Holmes finds blood on porter Eddie Hawthorn, who blames an accident. William reveals hidden blood evidence, forcing a confession. He admits to Louis he planted the evidence to speed up results, outmaneuvering Holmes. Defeated, Holmes asks Watson to continue assisting him. Meanwhile, Holmes' brother Mycroft meets Queen Victoria regarding missing documents tied to a national secret and receives royal authorization to retrieve them by any means necessary.

A Scandal in the British Empire, Act 1

A Scandal in the British Empire, Act 2

A Scandal in the British Empire, Act 3

The Phantom of Whitechapel, Act 1

The Phantom of Whitechapel, Act 2

Uproar at New Scotland Yard

The London Merchant

The White Knight of London, Act 1

The White Knight of London, Act 2

Mary's Sign

The Pair of Culprits

The Final Problem, Act 1

The Final Problem, Act 2