Just as Kindaichi is preparing to visit a mountain hut that is owned by Reika Hayami's father after receiving a letter of invitation, Miyuki finds the letter and insists on tagging along as well, and so they head over to the Takamaki Ski Resort in the Aomori prefecture, where the mountain hut in question is located, unaware that a mystery murder case is about to unfold — one that will force Reika to confront her own past.