Piku Banerjee is a Bengali architect residing in Delhi, with her 70-year-old father, Bhashkor. Bhaskor has problems with chronic constipation and traces every problem to his bowel movements. His habits often lead to quarrels with the servants and irritates Chhobi Mashi, who often visits them. Piku loves her father and, as her mother has died, takes good care of him but gets extremely irritated with him at times because of his eccentricities. Her colleague, Syed Afroz is a good friend, and she is a regular client of Syed's friend, Rana Chaudhary's taxi business. Rana has his own family problems with his mother and sister.
Piku wants to sell their ancestral home in Kolkata, Champakunj, but Bhaskor objects vehemently and decides to go to Kolkata. Piku has to accompany him, since she cannot let him travel alone. Bhashkor brings up his constipation problem and decides to travel by road. Due to Piku being very problematic with other drivers of Rana, they back away before Piku's trip. Piku, disappointed with the agency tries to book a flight, but soon, Rana arrives at their home to take the family to Kolkata himself, without informing his family about the trip.
On the way, the group encounters many incidents, including Rana on the verge of losing patience due to Bhashkor's fussy behaviour and constipation. They finally reach Kolkata, where Piku's relatives live in the old house and Bhashkor asks Rana to stay for some time. Piku and Rana go out in the city and gradually grow close. Rana also subtly hints not to sell the house during a discussion.
Rana leaves Kolkata the next day and asks Bhashkor to stop his eccentricities which he eventually listens to. Piku changes her mind and decides not to sell the house. Meanwhile, Bhashkor's sudden desire to bicycle increases as he cycles through a part of the city alone, leaving everyone tense since he did not tell them about it. When Bhashkor returns, Piku berates him for eating street food and for being irresponsible, but he simply states that his constipation is cleared and he needs to bicycle every day. He remembers Rana who had told him to eat everything and not be choosy and picky about food. Piku is secretly happy but does not emote much.
The next day, everyone discovers that Bhashkor has died in his sleep, probably from sleep apnea or cardiac arrhythmia. Piku states that he always wanted a peaceful death. She returns to Delhi, where she arranges his funeral. There, Dr. Srivastava, Bhashkor’s doctor, reveals to her that Syed, too, has constipation and Bhashkor knew about it for a long time. A few days later, she pays up whatever due she owes Rana. She renames the Delhi house "Bhaskor Villa" in her father’s memory and the maid, who had left due to Bhashkor’s tantrums, returns to work.