"Only Yesterday" centers on Taeko Okajima, a 27-year-old unmarried woman living in Tokyo, who decides to take a trip to the countryside to assist with the safflower harvest. The journey becomes a catalyst for her to reflect on her childhood, particularly her experiences as a fifth-grader in 1966. The narrative alternates between her present-day travels and flashbacks to her younger self, exploring themes of identity, memory, and self-discovery.

In the present, Taeko interacts with rural life, forming connections with the locals, including Toshio, a young farmer who shares her appreciation for the simplicity and beauty of the countryside. Their conversations and experiences contrast sharply with her urban life, prompting her to reevaluate her choices and aspirations. The flashbacks reveal pivotal moments from her childhood, such as her struggles with academic pressure, her first crush, and her evolving relationship with her family. These memories are not merely nostalgic but serve as a lens through which Taeko examines her current life and decisions.

The dual timeline structure allows the story to delve into Taeko’s internal conflicts, particularly her feelings of inadequacy and her desire for a life that aligns with her true self. The juxtaposition of her childhood innocence and her adult uncertainties highlights her growth and the lingering impact of her past. By the end of the story, Taeko’s reflections lead her to a deeper understanding of herself, culminating in a decision that signifies her acceptance of both her past and her present. The narrative is grounded in realism, focusing on everyday experiences and emotions, making it a poignant exploration of personal growth and the passage of time.