Sad Sonata is a love story about two men and one woman. The young Joon Young, who was raised by his mother who sold liquor to American soldiers, met the blind Hae In and they became childhood sweethearts. Then, Hae In immigrated to the U.S. following her aunt and her uncle, an American soldier that married her aunt. There she met Gun Woo, who was Joon Young's best friend and the son of a very rich man. After she received a letter from Hwa Jung saying that Joon Young is dead, she accepted Gun Woo's love. After an operation, Hae In was able to see again . The story picks up again when composer Joon Young, singer Hae In, and music producer Gun Woo all meet again.