Knowing this will help me give you more specific details about the culprit or the clues! Detective Conan Rewatch: Episode 136-137
If you are following the Japanese numbering (which some Italian streaming platforms or fan-lists use), cover a fan-favorite "survival" mystery. Stai guardando DetectiveConan Ep 136-139 ITA
Conan disappears early in the episode after finding a secret passage, leaving Ai Haibara and the other children to solve the mystery of the castle's hidden treasure and a series of disappearances. Knowing this will help me give you more
A new girl named Ai Haibara joins Conan's class. She eventually reveals her true identity as Shiho Miyano (codenamed Sherry ), the scientist who created the APTX 4869 poison that shrunk Shinichi. Stai guardando DetectiveConan Ep 136-139 ITA