The story takes place in the fictional town of Plassans, somewhere in Provence, and centers around three branches of a family that originates with Adelaide Fouque, child of a wealthy family with a genetic history of mental instability. Adelaide married a peasant by the name of Rougon and had a son named Pierre. When her husband dies, she scandalizes the town by having an affair with a local smuggler and alcoholic named Macquart and has two children with him, Ursule and Antoine.

A lot of the book traces the history of the Rougons and Macquarts. Pierre takes over the family's finances and starts a family with a merchant's daughter whose appetite for scheming and social climbing matches — even exceeds — his own. Ursule marries a stable middle-class hatter named Mouret and dies after having three children. Antoine spends most of his adult life not working and extorting what money he can from his own family.

Equally important to the progression of this series as the family tree is the historical context. This novel takes place in 1851 and concerns the coup that resulted in Louis-Napoleon Bonaparte becoming Emperor Napoleon III, although the action centers around the republican resistance in Plassans rather than the political upheaval in Paris. This is where I should note that if you're not interested in French history, you will probably not like this book. The introduction provides some useful background, but I did quite a bit of outside reading to understand what was happening.

This is a story about the beginning of the French Second Empire as seen from a small rural town in Southern France, about young love and naive idealism crushed by authoritarian might, and about some pretty despicable but very authentic characters who are left standing with blood on their hands when the smoke clears.