Kogoro receives a request from literary critic Takahiko Kamiyu to stay at his house while he goes to the countryside for three days. He plans to turn down the offer, as it doesn't seem like detective work, but for the high pay, all he has to do is look after the pet cat, and the only thing that bothers him is the noise from the construction work that starts on the second day. Kogoro accepts the favorable conditions, which include free use of alcohol and food in the house, and the right to invite Conan and Ran. However, while he is relaxing at the Kamiyu residence, one visitor after another begins to arrive...