Swaroop, a young Muslim boy from a caste of musicians, leaves his desert village in search of work with his Uncle Nizam. Swaroop is an innocent and curious 14 year-old boy who is discovering the world outside of his isolated village. Nizam takes opium regularly and scams money in any way he can. Swaroop and Nizam travel together, join Nizam's musician friends, and perform at roadside locations along the way.

Nizam's greed and use of religious rhetoric lead to the break up of the small group of musicians and eventually to Swaroop heading off on his own in the city. Swaroop tries to adapt to his ever-changing circumstances of being a traveling musician in a world he has just discovered.

In the city, Swaroop meets Santosh, a young Hindu boy studying to become a priest. Santosh decides to join Swaroop to become a musician. The two boys quickly find themselves in a world of malls and multinationals.

Milk & Opium leaves the viewer questioning what will become of Swaroop and traditional India. The film features outstanding traditional Sufi music with a twist of fusion. All of the actors play themselves in a unique neo-realist style cinema.