Its a story of a lower middle class happy nuclear family. The lady of the family gets involved in prostitution, owing to the not so good financial condition of the family. It is the story of the guilt that comes with the money and the cobweb that such a route entails that its quite an effort to come out of the profession once one enters it.
This movie has many things to take it from, but lets first discuss the story line. The story line is quite weak at times. The most important scene of her starting all this is unconvincingly shown. However one may argue (and I argued the same thing with myself when I saw it the second time) that this is how it looks like if someone watches a real person go through all this. It feels unconvincing. And thats how it feels in the movie.
But other than some of that, the movie and many dialogues have far reaching connotations. The movie talks about man's endless desire to acquire, rather beautifully. It tries to separate needs and conveniences. It also touches on the sexual imbalance existing between couples. One line that I always remember from this movie goes something like this "Slowly and slowly husbands and wives start sharing their habits much more than they share their thoughts and this distances them".
Anyhow, this is a not a great one, but a worth see anyway. It might not be the full money's worth but it might initiate a much needed thought process.