Asylum. It is a Wonderland filled with peculiar residents. The Mad Hatter who always wears a hat, the Cheshire Cat who constantly smiles, the Queen who bosses everyone around, and the Caterpillar who can only squirm. Into this mysterious land comes Alice, a girl with a love for imagination. In 1889, England, while the serial killer "Jack the Ripper" is causing an uproar, Alice and her companions are living their usual strange days at an asylum on the outskirts of London. Then, one day, as Alice and the others are playing croquet, a commotion occurs. "The caterpillar is dead!" Only four people could have killed the caterpillar: Alice, the Mad Hatter, the Cheshire Cat, and the Queen. Alice is shocked, the Mad Hatter is confused, the Cheshire Cat smiles, and after some thought, the Queen solemnly declares, "If the culprit is among us, they must be caught immediately. We need to identify and restrain them." Everyone nods in agreement and decides to discuss the matter."

—For someone like you, solving a case this small should be a piece of cake, right? You wake up in a room you've never seen before. You have no memory of how you got there. Prrrr… Prrrr… Following the sound of the continuous ringing, you move toward its source—and find...

"To those of you who lack the courage to die alone. Shall we die together? I'm waiting for those who are interested to contact me." Date: XX Month, 20XX. Somewhere in Tokyo. - Inspired by a post on a certain social media, six people seeking to end their lives gather. At the arrangement of the organizer of the suicide meeting, they will have a final dinner before leaving this world together before dawn. However, it turns out that the six cannot die together; the organizer is discovered as a corpse. Did the organizer commit suicide? Or... was the person murdered? Amid various speculations, the remained five begin to debate.

Ryu and Sen, who live in Japan, join an event "English Puzzle Club" and will solve a puzzle while speaking in English.

Detective and Assistant visited the villa of Mr. Parker, the president of the town's newspaper company. However, a few hours later, he was found dead.