Captured by a ruthless gang of bank robbers, foes Diabolik and Ginko find themselves facing certain death. While Eva Kant and Altea forge an unlikely alliance to rescue their lovers, Diabolik reveals his mysterious past to the Inspector.
A message has arrived from Kid the Phantom Thief, that he will steal a Japanese sword belonging to wealthy Onoe Family in Hakodate, Hokkaido. Conan and Heiji Hattori, who happened to be in Hakodate, are on the case to capture Kid. Coincidentally the family lawyer of Onoe is found murdered in the warehouse district, apparently slaughtered by a Japanese sword. The suspect is an investor/arms dealer who is said to be after Onoe family’s hidden treasure. In the North among cherry blossoms, the exciting hunt for treasure begins!
Thirty years ago, hardened criminal Yip Siu-tin is arrested for armed robbery and sentenced to prison. Siu-tin’s daughter, who has handled the loot, changes her name to Cheung Sum-yuet and starts a new life. She also gets married to yacht company boss Yen Ho-yin. Meanwhile, Chong Chi-kiu is a kid left behind by an accomplice who has died because of the robbery. Kind-hearted Tang Sing-him becomes his foster parent. A traffic accident causes Chi-kiu and Sum-yuet to run into each other again. But this accident somehow has something to do with Siu-tin, who is just released from prison. Sum-yuet can no longer avoid Siu-tin, who is a nightmare to her. Her marriage also has certain issues. Police officer Yeung Yan-hiu intervenes by launching an investigation, and she keeps going after Siu-tin and Chi-kiu. Unresolved grudges for thirty years are again put on the front burner. Everyone implicated in a robbery of yesteryear is drawn into this mess.
Diabolik narrowly escapes Inspector Ginko's latest trap, leaving his partner in crime Eva Kant behind. Furious, Eva offers Ginko her help in capturing him, but the former has to face first the return of an old flame of his, noblewoman Altea.
1960s, the city of Clerville. The forthcoming visit of heiress Eva Kant, who'll be bringing a famous pink diamond with her, catches the attention of Diabolik, the infallible and elusive thief whose real identity is unknown: while trying to steal the jewel, he finds himself bewitched by Eva's charm, a feeling she may be reciprocating. But the police, led by relentless Inspector Ginko, is rapidly closing in on him...