Mitani Tokino runs a watch shop, but that is not her only business. She also uses her merchandise and mental prowess to crack alibis. A local cop is neither having much luck in life nor in the case on which he is working. He does not like to believe in amateur help or the involvement of outsiders, but stuck and with nowhere to go he yields and asks the shopkeeper for help. Tokino charges a price for her services however. She needs to make money too.