A serial blackmailer is found dead. An office worker he was blackmailing admits she did it, but Kogoro saw her in another neighborhood during the time of the murder. Why did she admit to a murder it was impossible for her to commit or is she hiding something else?

Kogoro drives Conan and Kei down a seaside highway. Six months earlier, Remi hanged herself in her apartment. Her neighbor Kei blamed herself for being unable to prevent her suicide. Now Kei has moved and is working at her uncle's resort inn. Kei is showing Kogoro and Conan around the local area. Remi used fake names to flee from debt collectors. Conan finds it strange that she used her real name to rent an apartment just before she died. He notices a few other strange things about the story as well...