Kosuge, the president of a factory, is killed by someone while returning home. A bag charm is found at the scene. When Akira Higuchi and his colleagues from the Metropolitan Police Department's Investigation Division investigate his home, they find a bankbook with the letters A, Y, M, and S written in English. It turns out that the charms left behind were custom-made by Seiji Iwai. However, Seiji had committed suicide five years ago in a robbery-suicide case. Seiji's mother, Mizuki, is an old acquaintance of Superintendent Tendo. Higuchi heads for Mizuki's place...

""Renjou" is the 11th special episode of the long running Japanese TV franchise Keishichou Kyoukouhan-gakari Higuchi Akira (transl: "Akira Higuchi, Tokyo Metropolitan Police Department")"