Ireland, 1849. The country is currently amid the Great Famine. Caused by a potato blight, hundreds of thousands have died due to starvation and other deadly disorders. Due to these circumstances, paying rent has become difficult for farmers, resulting in the eviction of many from their land. Two such people who got caught up in this dreadful situation are Amelia, a frail 14-year-old girl, and her servant Connor. Her family's land was taken away, forcing the pair to struggle while living as vagrants.

However, just across the sea, a rather profitable event is taking place—the California Gold Rush. With aspirations of becoming millionaires, Amelia aims to turn both her and Connor's lives around. They decide to travel to America, hoping for a life without ever needing to face hardships again. Katabami to Ougon is the story of two refugees as they venture outside of Ireland, with only their hopes and dreams pushing them forward.