Srinivasan (Mouli) is an owner of Ad Agency which is going on loss. To make his company stand up he expects a great project from big company Johnson and Johnson. During a meeting for project discussion Arjun (Ajmal Ameer) the art executive and a pet of Srinivasan, disappoints the clients with his mischief behaviour. To convince the clients who are reluctant to give the project to them, Srinivasan produces the ad at his own risk with his own money, on the agreement that the project will be accepted if done everything perfectly.
Thuruppugulan story is focused on Kochuthoma (Innocent) and his son Kunjumon (Mammootty). Kochuthoma is running a typical street side "thattukada" in Kochi. At the age of ten, Kunjumon accidentally injures a person. After the incident when his son faced trouble to stay at Kochi, Kochuthoma sent him to Kozhikode to stay with his dear friend Swami (Jagathy).
The story of the film goes through the time of H. Mehboob, who tell us the story of the slavers and Jews, who worked for the Dutch and Britishers who ruled over India. It tells us the songs of Cochin that go beyond caste, creed and nation.