Piku (Deepika Padukone) is an architect by profession and at the same time, she is also a daughter of an overbearing father Bhaskar Banerjee (Amitabh Bachchan). Bhaskar deals with constipation issues which is actually psychological than physical. Rana Chaudhury (Irrfan Khan) owns a taxi service which Deepika has hired to take her to and fro from her office. Now when no when agrees to take Bhaskar and Piku to Kolkata, his ancestral city after a sudden and severe breathing problem, Rana, decides to take them to Kolkata, even though he is hates every bit of it. The rest of the movie is all about their weird and interesting journey.