One day, Gimpel is shocked to discover his wife Elka in bed with another man. This is not the first time she's cheated on him, and it certainly won't be the last. The local rabbi orders Gimpel to get a divorce. But Gimpel, being a complete fool—hence the nickname—is reluctant to do so. Bizarrely, he manages to convince himself that he didn't really catch his wife in bed with another man after all; he must have been hallucinating.
For the next nine months, Gimpel sleeps at his bakery while the rabbi figures out a way to resolve the issue. He does so by a creative interpretation of the works of the medieval Jewish philosopher and Torah scholar Maimonides. Gimpel is now free to return home. But when he does so, Elka is in bed with yet another man, this time Gimpel's apprentice.