Yin Xiangtie (played by Lee Sung-jae), who has some power in a large company, originally had a happy life, but because of an affair with his female colleague Yin Songhua (played by Wang Ji-hye), his wife committed suicide, leaving behind the eldest daughter Han Jie (played by Kim So-hyun), the eldest son Du Jie (played by Cai Xiangyu), the second son Shi Jie (played by Nan Dalin) and the youngest daughter Hui Jie (played by Jiang Zhiyou) without anyone to take care of them. The gray-faced father survived the most difficult 49 days and invited the domestic service staff Park Bok-nyeo (played by Choi Ji-woo) through an intermediary to take care of his children and do housework. Park Bok-nyeo has a blank expression and takes care of everything in the house in an orderly manner. She can even remember many things that ordinary people can't remember. Han Jie's siblings resisted the arrival of Bok-nyeo, but they were also curious about the life experience of this mysterious woman. No matter what the master's order is, Bok-nyeo, who is like a robot, will execute it unconditionally. She will bring a huge impact to this home on the verge of ruin... This film is adapted from the 2011 Japanese drama "Housekeeper Mita".