Joo Hong-bin is a heartless and fearless man. He’s a smart, wealthy, prickly man who suddenly develops the ability to sprout iron from his body due to his painful heart and faces hardships for the first time in his life, he gets this power because of all the pain he carries in his heart, and discovers love and grows up along the way. Meanwhile, Song Hae-kyo is a meddlesome sort who loves the hero and takes it upon herself to turn him into a real man.