Magazine journalist Renji Himura is suspicious of the corrupt nature of Japanese politics and has uncovered a number of parliamentary scandals in his quest to clean up the political scene. His feud with his father, Tetsuya Himura, a member of the House of Representatives of the ruling Republican Party of Japan, reinforces Renji's aversion to political power struggles. Tetsuya is a member of the party's largest faction, the Teikankai, along with his ally Yuichi Tanigawa, who was elected in the same year, but becomes increasingly dissatisfied with the methods of faction chairman and former Prime Minister Shiro Oda. In order to regain the prime minister's office, Oda has brought in Kojiro Suzuki, the current prime minister, and is building a puppet government. Then, Renji receives a tip-off from a mysterious person.

Renji, who publicly revealed his father's allegations of illegal contributions during the election. Prepared for a firestorm on social media, Renji makes a speech to capture the floating vote and wins the ticket to the Diet in a stunning comeback, renewing his determination to become a "respectable" politician following his father's wishes. In addition, Prime Minister Suzuki resigns after allegations of bribery. The Republican Party's presidential election is about to begin. Only five new members of the party can influence the outcome of the presidential election. Then, Renji receives a phone call from that person again.

Renji goes to see his father to question Tetsuya's allegations of black-market donations that arose when he launched the Shinseikai. However, Tetsuya's heart condition worsens and he collapses on the spot. Renji's father's death brings an end to the feud between father and son, and Tanigawa persuades him to keep the truth of the allegations to himself, and he decides to follow his father's wishes and become a politician. At the same time, Prime Minister Suzuki dissolved the House of Representatives and called a general election, as ordered by political fixer Oda. With Tanigawa's support, Renji launches his own political activities, but is outnumbered by his opponent, prefectural assemblyman Horiuchi. Renji is again contacted by a mysterious person.

Fumika, a culinary school student, receives an invitation to a mysterious tasting party from Shizuka Izu, a charismatic culinary researcher, and happily tries to attend. However, she is attacked from behind by someone and loses consciousness. The place where she woke up was a closed ruin. There were four men and women who were also invited to Shizuka.