Kiyotaka and Aoi are back from New York and enjoying their return to daily life at Kura. One day, they're visited by Kurisu Aigasa, a mystery author they solved an attempted murder case for in the past. She wants them to read a new novel she's written—with the protagonists modeled after some very familiar faces! Set in Kyoto in the early Showa period, The Tragedy of the Grand Family follows the detective Kiyotaka and his student Akihito as they try to solve the mystery of an extremely wealthy family.