Ran had a nightmare about her mother dying. And immediately checked on her by phone. She was fine and alive when Ran heard her voice. After telling her about the dream, Eri(Ran's mom) told her it was nothing. But Ran suddenly remembered an incident that occurred 10 years ago. Which was very similar to her dream and was the same time Ran's mom got divorced with her dad, Kogoro. And the same time Kogoro resigned as a police officer.
Meanwhile people that Ran knows are being attacked and injured by a certain culprit. Conan realizes that all the people who been attacked have a relationship with Kogoro. And each of them have a number in their names corresponding to playing card deck and were being targeted in order, from the king down to the ace. The police presumed it was the work of an ex-card dealer who's just been released from jail. Kogoro arrested that man 10 years ago, and it's most likely that he's forming revenge against Kogoro. It's a matter of time when the culprit strikes the other victims. And Conan will soon discover that this scenario is entirely different after he learns the truth about what happened 10 years ago.
This Conan is slightly more better than the previous one. It has a lot more to it for a sequel. Including a larger cast of characters. More locations, thrilling moments, and action filled scenes. The mystery is more well done too. In other words expect the unexpected while watching this one. In addition, we even get to learn more about why Eri & Kogoro divorced. Which is pretty funny when they get to that part.
In my opinion this is the first best Detective Conan movie, I've seen so far.