Takeshi Hongo is a promising young man with a passion for motorcycle racing. However, his dreams are suddenly ruined when he gets kidnapped by Shocker, the evil secret organization planning to dominate the world. After being remodeled into a cyborg, Takeshi escapes and swears to protect the world from the inhuman monsters.
When the rock band JoKers broke up one member flew over to be with the yankees and try to make a living there. Another one decided to focus on his schooling and become a university graduate instead of continue on with music. Two others are still hopeful their music career can be put back together. To rekindle all members' love for rock one of the members is hired to coach all-girl band Drop Doll. In the meanwhile, the girls are improving.
Tobita Tasuku's father, Jinpei left a letter and disappeared on the day of Tasuku's high school graduation. Due to his father's disappearance, Tasuku is now left with his father's huge debt while he is still unemployed. Tasuku decides to visit the Joker Detective Agency to find his father but the cost of investigation is too high. Tasuku later finds out that the tuition fees for attending the detective school is much cheaper than the cost of investigation. Seeing that he can get a job in a detective agency and find his father, Tasuku decides to enroll into the Joker Detective School and be a full-fledged detective.
