Nakano Hitomi is an ordinary employee who works for the Metropolitan Police Department’s General Affairs Section. Her job is to check the receipts for investigation expenses that the detectives pay in advance, but she is extremely sharp in detecting cases because she was raised by her father, who is a swindler.

When serial killings and injuries occur, she is also the first to realise that the victims' names are linked to a word game in which one victim’s name contains the last character of the name of the previous victim. Hitomi uses detective Togawa of the First Investigative Division, whom she became acquainted with after finding discrepancies in his receipts and scheming lawyer Shirai Shinnosuke who works his way into the favour of victims to find work that pays well, to get close to the truth of the case.

사건에 대한 촉이 매우 뛰어난 주인공이 경시청 서무계에서 일하던 중 어떤 사건의 피해자 이름들이 끝말잇기로 연결되어 있음을 눈치채고 사건의 진상에 다가가는 이야기를 그린 드라마