‘I, me or main’ revolves around Ishaan, a music producer who has commitment issues with the women in his life, feels a connection with Gauri, his next-door neighbour and that is when he begins to learn the importance of relationships.

Ishaan (John Abraham) a charismatic, good-looking music producer from Mumbai, lives a sheltered existence as the apple of his mother's (Zarina Wahab) eye, always protected by his elder sister Shivani (Mini Mathur). He stays at his girlfriend Anushka's (Chitrangda Singh) house and takes them all for granted. One day Anushka sends him out of her house due to his irresponsibility about their marriage. His new neighbour Gauri (Prachi Desai) comes into his life, and he begins to fall in love with her. Ishaan is forced out of his company, and Gauri encourages him to start his own music company. While Ishaan is working on his music, Anushka is pregnant with his child but decides not to tell him due to him being irresponsible. Gauri gets a scholarship to Paris, and Ishaan and Gauri decide to live there after his big launch.

On the day of the launch, Anushka starts having contractions and Ishaan, realizing his responsibilities, takes Anushka to the hospital where they have a baby girl. Gauri leaves for Paris understanding what is happening. Eight months later, Ishaan and his baby girl Diya are talking to Gauri who is returning soon, while Anushka is happily married to another guy!