While Mouri, Ran, and Conan were driving near the ocean, their car broke down. They stayed at lawyer Tachibana’s villa for one night. However, the next day… Right in front of their eyes… Mr. Tachibana’s boat capsized and he died. They found out that Mr. Tachibana was killed by someone with the initials T.K., who had been sending threats to him. Five years ago, Mr. Tachibana acquitted him of a crime. They thought he was Tatsuya Kumada, so they rushed into his apartment. But what they saw was… Kumada, the suspect… Suicide!?