Second Time Twenty Years Old is about Nora, a girl with dream of becoming a dancer since she was at high school. However, at age of 19, she decided to stop learning and married her husband, Kim Woo-Chul. After having children, Nora entirely focused on taking care of her family and gives up her dream. Twenty years later, Nora has chance to relive her 20s when she attends the same university with her son, Min Soo with the hope of becoming a wonderful wife and mother.