Sukumaran, his brother Mohanan and their mother belong to a middle-class family and live happily . Sukumaran is a supervisor in a construction company named JK Constructions and Mohanan is a shopkeeper. Mohanan has recently married Shylaja who is employed,from a rich family and good looking unlike Sukumaran’s wife Kanchana. Shylaja’s fortunate life with money and job makes Kanchana envious about her and Kanchana slowly starts causing problems in the family by finding unnecessary issues which affects the smooth running of a peaceful family life. Finally Sukumaran leaves their family house and starts living in a rented house as part of Kanchana’s requests. The rented house is located in a posh colony wherein the residents are very rich.
Soon Kanchana finds one or the other reasons to live in luxury which is not conducive with the economical conditions of Sukumaran who is just a supervisor in a company. To match their social status Kanchana lies to her new neighbours that her husband is an engineer in a construction company. Soon Sukumaran leans for her demands like buying expensive home appliances, arranging a dance master for their daughter and sending her to an English medium school, buying an old car (in which Sukumaran would meet with an accident thereby increasing their medical expenses and car repair charges) etc. The huge economical demands slowly crush Sukumaran and it finally affects him in the manner of creditors demanding their money back.
In order to meet their financial requirements Sukumaran finally decides to cheat his employer by forgery. The authorities soon come to know about the truth and one day, when Sukumaran is already under heavy economical pressures, the police arrive and arrest him. The next day, because of the ill reputation caused by the family the house owner drives Sukumaran’s family out of their rented house. At this point Mohanan comes to their rescue knowing about the situations where his brother has been led by the ill advice of his wife Kanchana. Mohanan arranges money by selling his wife's gold ornaments and repays the creditors. Sukumaran is finally released from jail. In the end the family is re-united where Kanchana understands her mistakes.
Thalayanamanthram is some of the finest films for which Sreenivasan penned. The film was a critical and commercial success. Sreenivasan has come up with other family stories which have their own relevance at their time and still. In Thalayanamanthram, if it is a wife's ill advises that causes problems in the family in another movie named Mithunam for which also Sreenivasan penned, it is a wife's romantic ideals and possessiveness toward her husband that cause problems in the family. A thing which the movie did not overtly tell but echoed is regarding the educational standards of the women in the families. Sukumaran's character who had opportunities for a better alliance chose to marry a woman like Kanchana who had not at least passed the secondary education. However, contrary to this Mohanan who did not have a white collar job like his wife Shylaja, managed to live happily without problems. Their mother played by KPAC Lalitha who probably had not much education as even Kanchana had, also is not responsible for any problems in the family. Hence the finger is not pointed toward the educational standards of women or on any particular gender but on the level of understanding and co-operation among family members which is necessary for a peaceful and prosperous family life.
Urvashi .... Kanchana (Wife of Suku) ( Voice dubbed by Bhagyalakshmi)
Srenivasan as sukumaran
Innocent as t.g daniel
Mammukoya .... Kunjanandan Mesthiri
Sukumari .... Sulochana Thankappan
Meena.... Gigi Daniel
T. P. Madhavan .... Manager
Oduvil Unnikrishnan .... Pothuval Mash
Jagadish .... Bhasurachandran
. with k.p.c Lalita as the mother of sukumar and mohan and jayaram as mohan Additionally Parvati as the wife of mohan and kollam thulasi as Raman kartha