It is the summer of 1941. An eastern-Finnish machine gun company receives an order to turn in their surplus equipment. The company is transferred to the front lines. The next morning the soldiers wake to the sound of guns – the war has begun.

Niskavuori's Aarne (Arne från Niskavuori) is a Finnish drama film from 1954. It is based on Hella Wuolijoki's play Niskavuori's Bread. In chronological order of the Niskavuori series, the film is the fourth. Aarne has married Ilona and left the house in Niskavuori, which he hosts, where his former wife Martta still lives, while the old mistress is holding the reins. Aarne and Ilona live in Helsinki, but Aarne has not been able to completely break away from Niskavuori, but keeps secretly in touch with the headmaster and gives instructions on the farm management.

The everyday life of the small village is mixed when a fire breaks out the night after the party. The cooperative manager and fire manager alerts the young judge Heiki to the extinguishing work, but due to the confusion, extinguishing the fire turns out to be more complicated than expected.

An architect, who has recently married a new, younger wife, tries to re-connect with his ex-wife, who is being courted by another man.

The year is 1895 in a small village in Savo, where new ideas such as women's rights and folk high schools are vehemently opposed by Pastor Jussilainen, both in his home and in the parish. His wife Eveliina, the maids, and the conservative parishioners all experience his vehemence. However, the pastor meets his match when his mother-in-law arrives for a visit.

Marjatta lives in poor conditions in Tampere with her widowed father Arttu who works as a factory worker. Marjatta gets to know engineering student Pauli whose constantly worsening mental health problems and jealousy become a threat to Marjatta and her close circle.

Ilona, an orphan from the cruel Paksula family, ends up in Helsinki at a children's home for immigrants and from there becomes a foster daughter in the Orpana family, where she begins to sort out the relationship between her war-disabled stepbrother Pentti and his girlfriend Irene.

The last black-and-white film in the Niskavuori series of movies.

Justiina Puupää drives her husband Pekka and his friend Pätkä to look for work. The two decide to make money the easy way and try to have an accident after first getting accident insurance. After trying their luck, they hurt their heads and in the hospital, the comrades see each other's more outrageous antics.

Pekka Puupää and Pätkä, who return to Helsinki from an unsuccessful variety show tour, are forced into refresher training, where they are trained as frogmen. During the diving exercises, the friends encounter the mermaid Helmi, whom they help into the bathtub at home, to Justiina's shock. The friends, who have become civilians, eventually end up on a plane bound for Suez, being cornered by UN soldiers.