At 25 years old, Kakushidate Yakusuke is plagued by a curse that has him constantly stumbling into crime scenes and being charged as the main culprit. In a last-ditch effort to prove his innocence, he seeks the help of Okitegami Kyouko, renowned as the "Fastest Detective." However, Kyouko suffers from an uncommon form of amnesia which wipes her memory of the previous day every time she dozes off, leaving her with just 24 hours to crack the case.