Richard is invited to Rika Okano's ikebana award ceremony to investigate a threat letter announcing a murder. Rika brushes the letter off as jealous hate mail, but the threat soon comes true when the owner of the hotel where the award ceremony is taking place is strangled to death. Conan notices something strange about the flower the owner was wearing and figures out the trick after he finds chloroform in Rika's dressing room. He also finds cyanide and worries that another murder will take place. Conan hurries to the stage where Rika is performing and sprays all the flowers with liquid nitrogen. With Richard stunned, Conan reveals Rika's manager to be the culprit who also made a suicidal attempt to take Rika's life as well.