Old in Age, Young at Heart summary: Go Seon-yeong, who was once a successful actress, has now fallen to being a housewife with a cheating husband and three immature sons. One day, she visits a fortune teller recommended by an acquaintance, and receives a talisman along with the words, "Your husband cheated because you've grown old and ugly. If you want to become young, have a relationship with a young lady." Seon-yeong, who is extremely stressed due to her appearance complex and her husband's affair, judging that the shaman's 'relationship with a young lady' was 'sexual intercourse', and ends up sleeping with the new housekeeper...