The story revolves around a 38 years old housewife, Ha No Ra (Choi Ji Woo), who decided to go back to school and experience the college life for the first time. She spent the last two decades as a housewife after she got married and became a mother at the age of 19 years old. Her 20 years old son, Kim Min Soo (Kim Min Jae) and his girlfriend, Oh Hye Mi (Son Na Eun) are her classmate, while her husband, Kim Woo Chul (Choi Won Young) and her first love, Cha Hyun Suk (Lee Sang Yoon) are the professors in that college.
Detective Cheo Yong (Oh Ji Ho) uses his abilities to interact with spirits to solve cases.
Do Hae Kang (Kim Hyun Joo) involved in a mysterious car accident. Due to this car accident, she loses her memory and falls in love with her husband, Choi Jin Uhn (Ji Jin Hee) whom she hated again. She then meets her separated twin sister Dokgo Yong Ki for the first time in 30 years.
Oh In Yeong is a former idol group singer. She belonged to a popular 4 member girl group, but, now, she isn't very popular anymore. In order to boost her flagging popularity, In Yeong agrees to appear in a television reality show that pairs up fake mothers- and daughters-in-law. While filming for the TV show, she meets her scripted mother-in-law Yang Chun Ja, a matriarch of a long-standing traditional clan. They end up hating each other on the show, but as fate would have it, the two later end up becoming mother and daughter-in-law for real.
A story about the tiring but sad love and hatred between a mother and her daughters. Lee Jin Ae (Eugene Kim) has a love and hate relationship with her mother, Im San Ok (Go Doo Shim). She dreams of becoming independent from her family and especially from her mother. Jin Ae falls in love with Kang Hoon Jae (Lee Sang Woo) and marries to him. Meanwhile, what awaits for Jin Ae is her new mother-in-law, Hwang Young Sun (Kim Mi Sook). While experiencing difficult times with her mother-in-law, Jin Ae begins to understand her mother San Ok for the first time.
Kim Tae Hyeon is a talented surgeon. Desperate for money to pay his sister's medical bills, he adopts the code name Yong Pal and offers his medical skills to those in need of medical attention but who cannot do so publicly, dealing with gangsters and corrupt plutocrats. It is while making such a house call that Tae Hyeon rescues "sleeping beauty" Han Yeo Jin, a chaebol heiress, from a medically induced coma, leading to unintended consequences.
Choi Yeong Jin is a female detective squad chief. She also raises her daughter Ha Eun. At work, she deals with brutal crimes with her senior detective Park Jong Ho and squad members Min Do Yeong, Han Jin Woo, Jo Jae Deok and Lee Se Won.