Sacred Love Island Murder Case, also known as Seiren Island Murder Case (聖恋島殺人事件 Seiren-tou Satsujin Jiken), is the second and the third episode of the fifth generation of TV Drama series The Files of Young Kindaichi. It adapts the story arc of the Sacred Love Island Murder Case from the Returns Series.

In these episodes, Hajime Kindaichi, Miyuki Nanase, and Ryuta Saki invite by Inspector Kenmochi to assist him on a fishing tour at Seiren Island. When they arrived, the murder happened committed by a legendary Siren, the Sea Monster, that lived on that island.