Lupin and his companions have been using the mansion of a noble named Saint-Germain as their hideout. When Cardia meets Saint, he makes a comment that seems to carry a deeper, hidden meaning.
A phantom thief has been appearing all over London, stealing treasure only from vampires. As the case involves vampires, Van springs into action. Cardia wants to help as well, and they set out to capture this phantom thief.
Lupin and the rest move forward with the plan to capture the train Finis is riding. Lupin and Cardia board the train in disguise, and all seems to go as planned until a man appears before Lupin.
Thanks to Finis, Lupin and the others are on the wanted list after the train explosion, making their search for information on Isaac difficult. Fran shuts himself up in his lab, making Cardia worry.
A mafia-sponsored airship race is being held, and first prize is the posthumous writings of Isaac Beckford. Lupin and the others believe the writings might give them some clues about Isaac, so they enter the race.
Van and the others' search for Cardia in London is interrupted by an explosion! Isaac's terrorist plot has begun and a coup d'état within the British Army endangers Queen Victoria.
Finis has taken over London through a coup d'état as he moves forward with the Code: Realize plan. Meanwhile, Saint appears before Cardia and identifies himself as a member of Idea.
The British Army marches on St. Paul's Cathedral, Twilight's base. As a diversionary force, Lupin and the others have infiltrated the cathedral, but waiting inside is Aleister, Van's former superior.
Cardia has been captured aboard the Nautilus. Lupin and the others want to help her, but they're helpless in the face of the massive flying fortress. Lupin tries to board it himself, but Van stops him, reminding him that he's injured.
Cardia is absorbed by the celestial sphere, and while inside it, she sees her father's memories. Among them is the event in their past that pushed him over the edge into madness.
