An accident awakened Karamatsu's special power, which allows him to understand the inner words of mice and insects. One night, the mouse in the house brought important news about an accident next door, giving her the first clue to the case. Relying on microscopic information that ordinary people cannot obtain, she can always capture the clues missed at the scene and assist the police in solving many difficult cases one after another. At first, everyone was dubious about her unique approach to investigating cases. However, as many cases were successfully solved, she became the police station's exclusive special investigation consultant with her solid results.
