Conan and Kogoro met Takayuki Katsuro, an accounting firm manager, his wife Sayaka Katsuro, and his secretary Ken Makinoura at the hospital. Takayuki had been diagnosed with only six months to live, but he seemed to be trying to live his remaining time to the fullest. A few days later, however, he is found murdered in his home. That morning, Sayaka and Makira went out to run an errand for Takayuki. When they returned home in the evening, they found Takayuki in the bathroom with his wrists slit. It seemed under the circumstances that he might have cut his own hand, but Sayaka and Maki-ura, as well as Conan and the others, believed that he was not the kind of person who would do such a thing because he was suffering from an illness...