Johanna Tähtinen's husband Ykä burns down their house and goes to jail so Johanna and daughter Liisa are left with nothing. Johanna, not being very intelligent, doesn't know what to do, so it's up to Liisa to find them a place to live. In the meantime mother-less teens Matti and Missu get tired of taking care of the house and their scientist father, widowed Hannu Hurmala, and put an ad in the newspaper to find a housekeeper. Liisa spots the ad which promises also an apartment. Matti and Missu, desperate, hire Johanna without asking their father. Hannu, dating super-jealous school teacher Margit Haukkamaa, isn't happy about the new housekeeper and her daughter...—Sephora