Mariyaan story begins with Mariyaan (dhanush) who works as a contract fisherman in Sudan, Africa. After two years of toiling very hard he begins to prepare to return home to India and reunite with his ardent ladylove Panimalar (parvathi menon). But thigns take a turn when he gets kidnapped by Somali terrorists and ransom is demanded from his company. As the torture begins, Mariyaan’s thoughts of Panimalar intense and he decides to rbeak loose. What happens from there forms the rest of the story.