Detectives Don't Sleep

A woman named Nishiwaki Kae arrives at the Mori Detective Agency where Conan and Kogoro are. She explains that someone has been breaking into her apartment while she's at work and asks Kogoro for help. The intruder, who began breaking in a month ago, apparently is not a thief, but leaves gifts for her. The three of them head to her apartment and discover a suitcase with a ribbon on it in the entryway. Believing it is a new gift from the intruder, Kogoro opens the suitcase and finds a dead body packed inside...