Koodi Vazhnthal Kodi Nanmai

Thangaraj, Meenakshi, Sivaraman, and Krishnan live together in a single house, forming a close-knit joint family. Sivaraman's improved finances begin to shift family dynamics as he becomes the main breadwinner. The arrangement pleases Valluvardasan, who is impressed by the family's values and decides Tamilselvi should marry Sivaraman.

Valluvardasan takes a liking to Sivaraman and decides Tamilselvi, his daughter, should marry him despite their different social status. The plan is discussed with the elders and accepted by Sivaraman's parents, though it stirs questions about class within the extended family.

Tamilselvi, though from a wealthy family, shows respect for all members of the joint family. Kanagavalli is initially skeptical that she will mingle with everyone, but Tamilselvi's behavior gradually earns trust. This helps ease the tensions that might threaten the marriage arrangement.

Sivaraman's increased earnings make him feel like the primary provider, and he expects obedience from other family members. This shift strains relations, especially with Krishnan who has political aspirations. Quarrels erupt over control and responsibility.

Dhandapani, Thangaraj's neighbour, falls in love with Padma and seeks to marry her. Thangaraj decides to arrange their wedding, seeing it as a chance to keep the family together. The proposal triggers discussions about dowry and finances within the family.

Veerapandi, Dhandapani's father, demands a huge dowry for Padma's marriage. Thangaraj and Krishnan agree to provide the money, hoping Sivaraman will contribute, but he refuses. The rising tension triggers a major clash among the family members. The situation threatens the unity of the household.

Meenakshi feels hurt by Sivaraman's prioritization of money and leaves the house with Padma. Thangaraj also leaves, reflecting the fracture in the joint family. The home no longer functions as before, and relationships fray.

Tamilselvi learns the gravity of the split and seeks out Meenakshi. She apologizes for her husband's behavior and offers to provide the money needed for Padma's wedding. Thangaraj remains furious and resistant, doubting Sivaraman's changed attitude.

Tamilselvi, Meenakshi, and Kanagavalli join forces to ensure Padma's wedding to Dhandapani proceeds. They coordinate with Thangaraj and work to bridge the gap caused by Sivaraman's downfall. The collaboration shows the strength of the extended family when united.

With the women's intervention, Padma and Dhandapani marry. The ceremony marks a turning point as the family forgives past offenses and comes together to support the couple. The wedding stands as a symbol of the unity being rebuilt.

Thangaraj's coworkers confront Sivaraman and beat him for his arrogance and obsession with money. This public rebuke makes him realize his mistakes and he begins to apologize to his family. The incident becomes a catalyst for reconciliation.

Following the confrontation, Sivaraman apologizes, and the family reconciles. The joint family returns to its former harmony, with bonds restored and everyone ready to move forward together.