Ooka Momiji's Challenge (Part Two) At the request of Momiji Ooka, Conan and Heiji are trying to solve a cipher left to his four sons by a housekeeper who worked for a wealthy family for many years. Conan and Heiji arrive at Warehouse No. 4 in the port of Cupido, where they find a man bleeding from the head and three others lying on the floor. They are the four brothers who were left with the code, and the dead body is the eldest son. They were summoned by the eldest son, and when the second son who came first found them, they were already dead, and then the third and fourth sons joined them. From the appearance of the metal-framed glasses that had fallen nearby, Conan and Heiji believe that this was a murder.