'Unnodu Oru Naal' is a realistic and provocative thriller that explores the concepts of friendship, love and betrayal in the form of a triangular love story.
At the outset of the movie, Karthik and Madhav are friends. Priya comes between them when she initially falls in love with Madhav, and then changes her mind, turning her attentions on Karthik. When he comes to know, a heartbroken Madhav decides to flee the scene and goes abroad, while Karthik and Priya get married and lead a happy life.
Eventually Madhav returns to India, and meets with Karthik and Priya. Over a period of time, he tries to win over Priya's heart once more, placing her in an uncomfortable sandwich between her husband and her ex-lover. Their triangular entanglements gives rise to a shocking sequence of events that forms the crux of the movie.
In today's modern world, the young generation has been so deeply influenced by Western culture that they are easily led astray, and get tempted into indiscretions even after marriage. 'Unnodu Oru Naal' is a factual and evocative depiction of the disastrous consequences of adultery. 'One must have the discipline to never look upon another's wife,' this edict of the great poet Valluvar has been extolled and justified in this movie in a provocative and thrilling way.