The body of neighborhood nuisance Amagi is found in the park of a high class neighborhood. He was murdered around 9 PM the previous night. The body was stabbed numerous times by an awl-like weapon. Next to the body is the bloodstained medical examination card of neighborhood association president Bando. The police head to Bando's home to question him... but Bando has been poisoned with a combination of liquor and pesticides, and near the body is a bloodstained awl. Detectives Takagi and Chiba believe that after stabbing Amagi, Bando chose to end his own life, but...

While hiking, Conan and his friends meet campers Eiko, Ashizuka, Hayashida, and Takemi at a mountain cottage. The four of them have gathered to commemorate the death of their friend Motoki who accidentally fell to their death three years ago. Takemi, who camped by herself in a tent at the bottom of a cliff, is found murdered the next morning!