Samaru Ayuha is a high school student. She is honest and works hard at everything, no matter what. One day, she has trouble at a gyudon restaurant due to money. A man at the restaurant, Hiromitsu Yoshitaka, helps her out. The next day, she finds that Yoshitaka has come to her school as a substitute teacher for her ill homeroom teacher. Ayuha now believes that Yoshitaka is her fate in love. She keeps expressing her feelings to him.
Takada Yu is an employee of a development firm. His father has favored his high-achieving older brother and been indifferent to Yu since young. So Yu craves for his father’s love and wants his recognition somehow. Then one day, Yu encounters a woman. Although it was the worst possible meeting, he gradually starts to have romantic feelings for her through work and an unexpected development. But ironically enough, she turns out to be the girlfriend of his older brother. Yu begins to realize what he truly treasures and matures as a person as he struggles with this complicated romance and with his older brother and father.
Inspector Sugishita Ukyo, head of the Special Missions Division, returns from London and goes home in the sports car of Assistant Inspector Kanbe Takeru, who has come to meet him at Narita Airport even though Ukyo did not ask him to. However, on the way home, Ukyo notices police officers from the Metropolitan Police Department conducting a crackdown outside the agency’s jurisdiction in Chiba Prefecture and gets suspicious. The police officers that Ukyo had seen were riding motorcycles. He lies in wait in a street with a dead end, but the motorcycle police have vanished into thin air. Ukyo is mystified and begins a thorough investigation. The Head of the National Police Agency’s Secretariat, Onoda Koken, appears before Ukyo, who has a bad feeling about what is going on. He tells Ukyo that Honda Atsuto, a revolutionist and senior leader of the leftist radicals “Red Canary”, has secretly returned to Japan.