Two years ago, Kyoichiro Kaga (Hiroshi Abe) was still a detective at the Nerima Police Station. At this time, his father (Tsutomu Yamazaki) was seriously ill and hospitalized, but Kaga never visited him, and the gap between father and son was difficult to break. On this day, a murder occurred in Kaga's jurisdiction. A 6-year-old girl, Harutai Yuuna, was killed by a junior high school student in a nearby residential area. The boy named Naomi (Yuuki Izumisawa) was bullied at school and shut himself up at home. In order to cover up their son's crime, Naomi's parents, Akio Maehara (Tetsuta Sugimoto) and Yaeko (Naomi Nishida), took great pains to move the body and falsify the scene. Despite this, the sharp-eyed Detective Kaga still saw the clues... This film is adapted from the original work of the same name by Keigo Higashino, and is a SP of the TV series of the same name.