The 60-year-old modern retired "female director of the county records office" passed away unexpectedly. With decades of hard-core memories of the county's hydrology, geology, genealogy, and military and banditry history, she traveled back to the late Ming Dynasty 400 years ago when there was drought and war, and possessed the body of a 20-year-old young lady from the largest clan in the county whose husband had just died.
Relying on the understanding of local historical data, the actuarial calculation of ancient tax laws, and the "reverse parenting/family governance methods" of a 60-year-old hard-core Chinese mother, he led a group of cowardly and selfish "ancestors" to save themselves in troubled times and mediate with warlords.
In the end, in the gaps of history, an isolated city was saved by force, which was originally recorded in history books as "the massacre of the city and the elimination of heirs".