Haruhi and the SOS Brigade attempt to find clues to the villa owner's murder. Yutaka, the owner's younger brother, is initially suspect due to having been seen leaving the island the previous day before the storm hit. Haruhi and Kyon head outside during the storm, but find nothing. While drying off inside a cave, Haruhi comes to a startling conclusion about the murder. They return to the villa and set to devising a plan to solve the mystery.