This is a truly beautiful film. The story is essentially this: a Hindu man and a Muslim woman from a small village in India fall in love and decide to marry. The villagers disapprove of this marriage to the point that they are ready to incite a riot. Given the circumstances, the man and woman elope to Mumbai (Bombay.)
Everything is okay there, and the two have twins, Kamal Bano and Kabir Narayan (the names are a mix of Hindu and Muslim, to represent their heritage.) The grandfathers (while still in the village) naturally argue with each other and vow to make the children Hindu (or Muslim, depends on who wins.) Suddenly, the 1993 riots erupt, and the whole family is caught in the middle. The twins are almost burned alive, but they survive thanks to police intervention. Both grandfathers show up in Bombay (out of concern for their children and grandchildren) and continue to compete there.
When another riot ensues, and the Hindu grandfather (and grandson) are approached by a group of Muslim men, the Muslim grandfather arrives in the nick of time and tells the men "He is my brother." Later in the film, one of the twins is separated from the other and is taken in for about a day by a member of the "hijda" community (this is a community in India that is essentially composed of eunuchs or hermaphrodites, but they wear women's clothing.) In a conversation with one of the twins, the "hijda" says "Religion is a way to God." The child asks him, "Then why are all of these people killing each other?" To this the man replies, "I have no idea. And I've been thinking about it for a long time."
You don't necessarily have to be Indian to appreciate this film, but I think it helps. The underlying message is that "We (as residents of India) should be Indians first and Hindu/Muslim/whatever second. The film also conveys the message of tolerance and humanity. It is really an excellent film.
