Sincheon Station Exit 3: Min-ji who just turned 20, lives on the street day by day, doing a part-time job she stumbled upon after running away because of a conflict with her stepfather. Then one day, Min-ji gets to know a newlywed couple, Mary and Soo-hyeok. The couple clothed Min-ji in warmth like no one else in the world, and as they took care of her in their different ways, Min-ji makes a statement of harsh determination.