A distant relative of Itsuki, Keiichi Tamaru, allows the SOS Brigade, along with Kyon's sister, to stay at his newly built island villa. On their first day there, they enjoy the facilities and play on the beach. On the second day, they are kept inside by a storm, and play in the games room. The next morning, Keiichi's brother Yutaka Tamaru goes missing, and the SOS Brigade members find Keiichi seemingly dead in his room.