Maappillai (Son in Law) is a 1952 Indian Tamil film directed by T. R. Raghunath under the banner of National Productions. The film features an ensemble cast consisting of T. R. Ramachandran, P. K. Saraswathi, T. K. Ramachandran, P. V. Narasimha Bharathi, P. S. Veerappa, M. N. Rajam, M. Lakshmiprabha, V. K. Ramasamy, K. A. Thangavelu, M. Saroja, M. S. S. Bhagyam, K. Lakshmikantham, Ragini, Kaka Radhakrishnan, C. S. Pandian, R. Balasubramaniam and T. K. Pushpavalli.

Plot

The film narrates the tale of a Madras city-based businessman (R. Balasubramaniam) in whose printing press T. R. Ramachandran works as an office boy. Fortune favours him, and he becomes a rich man and is hated by the son of the printing press, the villain (T.K. Ramachandran) who vows to destroy the new rich man and take away his wealth. Kumar (Narasimha Bharathi) is a popular medical practitioner of the city and a do-gooder. The villain’s sister Nalini (P.K. Saraswathi) is attracted to the doctor, but the villain gets her married to the hero. The villain plans to kill the hero and shift the blame to the doctor. What happens to his evil designs and how justice triumphs form the rest of the story.