The Asuda family, who are still grieving over their mother's suicide, hires a new housekeeper to take charge of the housework. They get Mita, a cold-faced housekeeper who does everything that she is ordered to do, even killing people, except tasks that requires her to smile or to reveal her past. During this period of time, the family becomes fragmented, as they each blame themselves for their mother's death. Mita helps guide the family through these problems, though she did not explicitly give them advice.

Eventually, the family manages to come to terms with their mother's death. They in turn help Mita to overcome her extremely traumatic past, the reason for which she cannot smile or speak her mind. Thanks to their constant care for her, Mita gradually starts to discover love again. However, Mita knows that she cannot become the stepmother of these children, and thus takes the drastic step of becoming a cruel and ultimately short-lived stepmother. In the end, Urara, the children's aunt, becomes their stepmother. Mita then revealed that she cannot work for them anymore, since she has found employment elsewhere. On Christmas Eve, They finally managed to make Mita smile during their last dinner together. With the family having found their priorities in life, Mita leaves the family on Christmas Day to work for yet another household.

Kaseifu no Mita (家政婦のミタ?, I am Mita, Your Housekeeper) is a 2011 Japanese television drama series. The story revolves around a family who is grieving over their mother's recent suicide. They hired Mita as a housekeeper to upkeep the house, which has been thrown into disarray. Mita, who is played by actress Nanako Matsushima, will do anything that her employer orders her to do, except smiling or revealing her past.
 
This television series was broadcasted from October 12 to December 21, 2011 as part of Nippon Television's Tears Wednesday time slot, which airs every Wednesday from 10pm to 10:54pm. On average, Kaseifu no Mita garnered a viewership rating of 25.2%. Its last episode garnered a viewership rating of over 40% when it was aired,[3] making it the highest watched show of 2011 in Japan (The last TBS drama breaking 40% viewing was "Beautiful Life" in 2000).Kaseifu no Mita won several awards, including the "Best Drama" award, at the 71st Television Drama Academy Awards. Despite the popularity of Kaseifu no Mita, the scriptwriter revealed that there will not be any sequels to this series.