100 years ago, the last remnants of humanity were forced to retreat behind the towering walls of a fortified city to escape the massive, man-eating Titans that roamed the land outside their fortress. Only the members of the Scouting Legion dared to stray beyond the safety of the walls – but even those brave warriors seldom returned alive. Those within the city clung to the illusion of a peaceful existence until the day that dream was shattered, and their slim chance at survival was reduced to one horrifying choice: kill – or be devoured!

On her 14th birthday, Anna Akechi meets a magical fairy and suddenly time-slips from 2027 to 1999! There, she befriends Mikuru, a spirited girl who dreams of becoming a detective. When mysterious thefts stir rumors of the Phantom Thieves, the two transform into Detective Precure, using courage, deduction, and friendship to solve cases and uncover the secret of Anna's journey through time.

A house in the countryside. Aya, a primary school student, is staying at her friend Minami's house. There, Aya notices Minami's strange behaviour. Gradually, she begins to feel the unique atmosphere of the house, which she doesn't know...