A chance encounter brought about by summer arrives unexpectedly. Three female friends, known as the “Seaside Cinderellas,” grew up together by the beach. Meanwhile, a male friend entered a top university in Tokyo to meet his parents’ expectations and pursued his own path while living as an honor student. Men and women from different worlds, who would not normally cross paths, meet fatefully on a midsummer beach. As they confront each other with their complex emotions and true feelings, they grow. Can these men and women overcome the invisible “gap” between them? This is a story that will make your heart burn passionately in a short but sweet and sad summer. With the warmth of human connections and the excitement of love. Under the midsummer sun, there are as many encounters as there are waves and as many love as there are grains of sand. And then, the miracle of the summer story is set in motion.
The "first penguin" is the courageous first penguin that dives into the sea filled with enemies. Iwasaki Nodoka is a young single mother with no money, no house, and no work. While Nodoka decides that she will do anything to eat, she meets a fisherman who offers her "10,000 yen to rebuild the coast". Thus, Nodoka now carries the dreams of the local fishermen whose lives are on her shoulders. Despite her limited knowledge of the fishing industry, Nodoka does her best working with the stubborn sea men, breaks through the old common sense and customs with her boldness, and creates a revolution in the industry.