Ponner Sankar is based on historical novel written by Kalangir M. Karunanidhi. Story is about the two warriors, both are brothers named Ponner and Sankar living in Kongu Nadu (present day Coimbatore, Erode etc..). This is a historical movie and these two warriors are even worshipped today at most of the above mentioned part of Tamil Nadu.
The movie is centered on a couple, Nader and Simin, and their 11-year-old daughter, Termeh. Nader and Simin are about to leave the country for good; however, Nader has a change of heart and decides to stay and look after his father who suffers from Alzheimer's disease.
This English-language adaptation of the Swedish novel by Stieg Larsson follows a disgraced journalist, Mikael Blomkvist, as he investigates the disappearance of a weary patriarch's niece from 40 years ago.