Aditya “Adi” Gunjal (Aditya Roy Kapur) comes to Mumbai to work for a gaming company owned by Prahlad Kakkar, aspiring to make it big in the United States as a video game developer. At Mumbai railway station, he spots a girl (Shraddha Kapoor) on the adjacent platform trying to jump in front of an approaching train. A horrified Adi gives her a shout. The girl then disappears. Adi moves into Gopi Srivastava’s house (Naseeruddin Shah), his elder brother’s senior, a strict, retired High Court judge living with his wife Charu (Leela Samson). Ok Jaanu 2017 full
Charu is a renowned Hindustani classical singer who suffers from stage two Alzheimer’s disease. On his first day at work, Adi is encouraged by his friend Bantee to pitch the idea of his game “Mumbai 2.0” to his boss. Adi impresses his boss and gets a deadline of five months to prepare a prototype to Los Angeles for a competition. Later, while at his friend Jenny’s wedding, Adi spots the girl from the station. The girl introduces herself as Tara. Adi learns that Tara is planning to pursue architectural studies in Paris, and he says that he dreams of becoming a big shot like Mark Zuckerberg. Adi and Tara strike a chord over their mutual presumptions on the dysfunctionality of the institution of marriage.
Tara also reveals that her antic at the railway station was a ploy to get rid of her ex-boyfriend, who desired to marry her. Subsequently, they hang out, exploring the city. The next day, Adi pursues Tara to Ahmedabad on her work trip. Tara takes Adi to Sabarmati Ashram, which she used to visit with her father as a kid. She discloses that her decision never to marry was incited by her parent’s broken marriage. Adi and Tara decide to live-in with each other before they go their separate ways for their respective careers. The two approach Gopi and Charu with their wish. Gopi initially strongly disagrees with their desire but then decides to give in when Tara impresses Charu with her classical singing ability.