Keitai Deka Zenigata Ai(2002)

Keitai Deka Zenigata Ai is a Japanese detective series following Zenigata Ai, a high school girl who leads a double life as a secret detective. Granddaughter of the Metropolitan Police Department's Superintendent General, she hides her genius-level intellect and exceptional intuition behind an ordinary student facade. Assigned by her grandfather to investigate difficult cases, Zenigata Ai partners with Detective Jun Godai to unravel mysteries that baffle conventional law enforcement. Her IQ of 180 and sharp instincts make her uniquely equipped to solve complex crimes. The series balances the tension of maintaining her secret identity while tackling increasingly challenging investigations alongside her trusted partner.