Sanju, a cheerful and laid‑back young man from Nagpur, spends his days with his mother Saru and a close circle of friends. Although he is reluctant to leave his hometown, he eventually agrees to move to Mumbai at his mother's urging, so that he can secure a decent job. He is put up at the home of Vishwanath Purohit, a long‑time friend of Saru's. On the train journey to Mumbai, Sanju crosses paths with Anu, a young woman who openly disparages Nagpur boys, leading to an awkward and embarrassing encounter between the two.
Upon arriving in Mumbai, Sanju discovers that Anu is none other than Vishwanath's daughter, and he is expected to stay under the same roof and drive her to college each morning. Anu initially holds a strong grudge against Sanju, but her opinion gradually softens as she witnesses his genuine kindness and devotion to his family. The two become close companions. Sanju also comes to know about Vishwanath's steadfast reputation for honouring every promise he makes – a trait that once led him to sacrifice Anu's dream of becoming a doctor in order to fulfill a commitment made to a dying friend.
Meanwhile, Sanju begins a romantic relationship with a colleague named Tanisha. However, when Tanisha proposes marriage, Sanju realises that his true feelings lie elsewhere – he has fallen deeply in love with Anu. Before he can express his emotions to her, Vishwanath arranges Anu's engagement to Aditya, leaving Sanju devastated. Over time, Sanju and Vishwanath develop a strong friendship, and Vishwanath pledges to remain Sanju's friend for as long as he stays in Mumbai. Sanju eventually confesses his love for Anu to Vishwanath, placing the older man in a painful dilemma: he must honour his word to Sanju and support his quest for Anu's affection, while at the same time protecting his daughter and discouraging Sanju's advances.
In the ensuing emotional turmoil, Anu reveals that she too has loved Sanju all along and begs him to elope with her. Vishwanath, frustrated by the entire situation, angrily tells Sanju to take her away and marry her. Yet on the day of Anu's wedding, Vishwanath is stunned to find Anu still at home, while Sanju has departed. Sanju explains that he chose to leave because he could not bear to embarrass or hurt Vishwanath, and because he ultimately trusts Vishwanath's judgment as a father. Soon afterwards, Vishwanath arrives in Nagpur with Anu and gladly gives the couple his blessing, convinced that Sanju will bring Anu lasting happiness.
