Leaning on each other through thick and thin, a trio of best friends stand together as they experience life, love and loss on the brink of turning 40. Cha Mi Jo is the head dermatologist of a clinic in Gangnam. She is a warm character who grew up in a wealthy environment with a caring family and everything she could wish for. Jung Chan Young dreamed of becoming an actress but ended up becoming an acting teacher instead. Although her way of speaking may seem blunt and harsh, the sincerity in her words makes her a character impossible to hate. Jang Joo Hee is a department store cosmetics manager. Due to her timid personality, she has yet to really experience a romantic relationship.