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.

Nana and Shota are a newlywed couple and Nana is 15 years older than Shota. Nana works as a designer and Shota works as a gym trainer. They both enjoy mystery. The newlywed couple then move to an apartment and they attend a resident’s meeting there. Nana and Shota become involved in murder cases that take place at the apartment. Residents get murdered one by one. Some residents have a motive, but those suspects have an alibi. Because of this, an arrest has yet to be made.