Thampi (Thilakan) retired as an accountant from Indian Railway in mid-1980s following his son's death leads a solitary life in his ancestral house. Thampi's grandson Bhasker a.k.a. Pachu (Jayaram) had completed his medicine studies from Bangalore. Thampi is excited when his grandson Pachu, comes along with his friends- Lopez (Rahman), Renjith Menon (Ashokan) and Krishnankutty (Ajayan) to spend his vacation with grandpa. Their presence brings joy and happiness into Thampi's house. Pachu is engaged to a girl, Bhadra (Kirti Singh) who happened to be the granddaughter of Thampi's friend. During the vacation Pachu and his friends often goes to the nearby beach for a swim. During one such visit Pachu and Lopez gets pulled into the ocean and only Lopez manages to escape. The Police and the locals conduct a rescue operation in the ocean but in vain. It is believed among the locals that whatever that is taken by the ocean is returned on the third day (as meant by the title of the movie). Thampi refuses to acknowledge the fact that Pachu is dead and puts on a brave face, consoling Pachu's mother, his friends and Bhadra. Eventually the body is found on the third day. The funeral is held on the same day and Pachu's friends gets ready to leave the day after. They all visit the beach one last time to say goodbye to Pachu where they see Thampi arriving with priests to perform the funeral rites of Pachu. While performing the "bali", senile Thampi who lost all his hope and out of despair he takes the rice ball/"balichoru" in his hands proceeds to the sea. To everyone's shock Thampi along with the "balichoru" submits himself to sea and commits suicide.