Yoon Joon Suh and Yoon Eun Suh were raised as siblings, unaware that a hospital mix-up at birth had switched them. The truth is revealed after Eun Suh's car accident uncovers a mismatched blood type. The girls are returned to their biological families, and Eun Suh's life changes drastically as she's left in hardship while the Yoon family moves to the U.S. Years later, Joon Suh returns to Korea, and fate brings the two former siblings together again.