While attempting to figure out what had happened, the remaining guests discover that their radio is not working, effectively leaving them stranded on the island with the culprit until the typhoon passes. They also quickly discover that Kinzo has gone missing as well. Battler and the rest of the family come up with the theory that one of the eighteen people on the island is posing as Beatrice in an attempt to claim Kinzo's inheritance. The three primary suspects are the servants, who have access to the entire mansion; Natsuhi, who was the last person seen with Kinzo; and Eva, who has the most to gain from the murders. However, after a heated argument between Natsuhi and Eva, they are unable to come to a definitive answer and return to their rooms. Later, Eva and Hideyoshi are found to have been murdered in their locked room.

Battler and Beatrice begin their debate of logic vs. magic from Purgatory when the Ushiromiya family members gather for their annual conference. This time, however, Beatrice appears in the real world as an important yet anonymous guest. During that day, Maria is left outside by her mother Rosa as punishment for constantly talking about Beatrice. When Rosa returns to save Maria from the coming storm, Beatrice appears before them and hands envelopes to both of them. Meanwhile, Shannon discovers Beatrice's devious intentions and decides to resist her. Later, when George proposes to her and asks her to give him her answer by the next day, she accepts immediately. During dinner, the siblings discover their guest to be Beatrice and eventually come to acknowledge her as a witch.

Eva is discovered by Rosa and leaves to discuss how Kinzo's gold should be divided among the siblings. The young Eva, however, refuses to share the gold and remains behind, declaring herself to be the head of the Ushiromiya family. Acknowledging the young Eva's achievement, Beatrice appears and dubs her the new "Beatrice", whom Battler deems to be an alter ego for the real Eva. Later, Eva falls ill, and Rosa takes a whining Maria outside to spare Eva from her tantrum. They are suddenly attacked by Eva-Beatrice, who repeatedly kills and resurrects them in bizarre ways. Beatrice takes pleasure in the scene, but ends up enraging Battler, who refuses to play with her any longer. Dejected, Beatrice confronts Eva-Beatrice and mercifully kills Rosa and Maria once and for all, ordering her successor to act more dignified and reasonable in the future.

Ange enters the Golden Land where she happily reunites Maria with Sakutaro and forces Beatrice to continue the game. Battler, however, has lost his soul due to his uncertainty of his own identity. Desperate to revive Battler, Ange confirms his qualifications as Kinzo's grandson, and reveals her own identity as his sister to him, successfully restoring him. Having broken the most important rule as a piece in the game to keep her identity a secret, however, Ange dies. With Battler's resolve strengthened and Beatrice realizing she cannot escape the game, the two engage each other in their final confrontation, with Battler's blue truth against Beatrice's red truth. Kinzo's spirit appears to protect Beatrice, but Battler dispels him in blue by confirming his death not only at the start of the fourth game, but every game thus far; however, Beatrice confirms in red that there are actually no more than seventeen people on Rokkenjima. Nevertheless, Battler manages to explain all four games through human means, while Beatrice is left completely skewered by his blue truth, but unable to die. Beatrice begs Battler to kill her and presents him the last mystery she is able to give: since Battler is the only person left alive on the island, and yet Beatrice is also there to kill him, Beatrice asks, "Who am I?" Understanding Beatrice's plight, Battler promises to solve her final mystery and put an end to her suffering. Bernkanstel and Lambdadelta, however, intend to keep Beatrice in the game, torturing her for eternity.