Effi Briest, always having been attracted to wealth, marries Baron Innstetten Geert, twenty-one years her senior. This man once courted Effi's mother, Louise, but he was not as well established in the aristocracy in those days as he is now. In Kessin with her new husband, Effi soon falls into a miserable life. He's never around because he tends to business overseas frequently. Effi's intimidated by her solitude. When she begins to see ghosts and tells her husband, he angrily dismisses her for fear of her ignorance negatively effecting his business reputation. In his absence, Effi takes company with a man named Major Crampas, a rival of Geert's, and a married man. They carry out an exciting affair for some time.
When Effi gives birth to her daughter, Annie, the Geert family moves to Berlin. Effi and Annie enjoy each other's company. Tragedy strikes, however, when Geert finds Effi's old letters to Crampas. He divorces her, takes custody of Annie, and arranges a duel of honor with Crampas whom he detests for being such a womanizer. Geert wins, killing his opponent. Right around this time, Effi's family, the Briests, disown her and cut her out of their will. They no longer want their name associated with Effi and her disgrace.
As the years pass, Effi misses her daughter. Annie, being raised by Geert, has been taught to resent her mother for affair and divorce. When the two meet several years later, Effi cannot overcome her daughter's hateful programming. Unable to bear the agony of her own daughter's disdain, Effi gives up any hope of every having a healthy relationship with her. She drifts into a deep depression and develops a "nervous disorder." Since their daughter is so ill, Louise and her husband take Effi back and care for her until her death. At the end, Effi instructs her mother to write to Geert to express her extreme regret over the affair and her desire to reconcile.
