In Episode 1 of "Tsuma o Dousoukai ni Ikasetara," the story introduces a married couple whose relationship is tested when the wife attends a school reunion. At the event, she encounters former classmates, leading to a series of events that challenge the boundaries of their marriage. The episode delves into themes of temptation, fidelity, and the complexities of marital dynamics, setting the stage for the unfolding narrative.