Kim Da Hyun is a warm-hearted middle-school teacher, who has little interest in wealth, and loves to helping others. One day, on the train, she aids an elderly gentleman, who finds this quite admirable. He turns out to be extremely wealthy, and decides she’s perfect for his favorite grandson, Lee Jae In. Jae In is a hot-tempered businessman who expects to inherit the family company. By writing a will saying he’ll give his entire fortune to the person who marries Da Hyun, the grandfather forces Jae In to meet with her.