Siddharth (Aamir Khan) is a Mumbai tapori, a boxing champion. His brother, Jai, makes money through a former boxing champion who now rules the community by terrorizing people and stealing money from innocent merchants. Siddharth saw his father's death when he was a child which mentally affected him throughout his life. His father's words remained with him, though he had only been with his father for a little while. Siddharth meets a young woman, Alisha (Rani Mukerji), who rides with a motorcycle gang and Charlie (Deepak Tijori). This is a flavor for some comedy and a brilliant scene in which Siddharth is running towards a train and as the train is only a few feet away he jumps out of the way.

Siddharth and Alisha meet for the first time and fall in love, and the typical love story follows. Siddharth meets another person who reminds him of his father, Hari. He learns a bit more from this man of wisdom and helps him in his truth. How he does this and the how the message Anyone can swim with stream but a true human is one who succeeds against stream, of Hari and his father is carried out is what the movie tries to convey.