This historical suspense film will depict the day before the "Honnoji Incident", which is known as the biggest mystery in Japanese history, and track this mystery. The story begins in modern Kyoto. Mayuko (Ayase Haruka), who is about to get married, lives in the Honnoji Hotel, an incredible hotel that can be connected to the Warring States Period. Here, Mayuko meets Oda Nobunaga, who is about to unify the world.