The "Patang" story is based on the popular adage that everything that glitters is not gold and that all that is black is not charcoal.
Rai Saheb Deen Dayal is a Chairman, Lala Motiram (a merchant), Shastriji (a temple pujari), Babu Himmatrai (a contractor) and Ramdas (a dedicated journalist with a passion for truth) the members of the municipality of a town called Basantpur. All of them, except Raj Mehra, are endowed with a Jekyll-and-Hyde personality: i.e. respectable exterior masking an evil mind.
Ramdas' daughter Shanti and Rai Saheb Deen Dayal's son Rajan are playmates since childhood. On a Diwali night, Shanti loses her eyes due to a slight negligence on Rajan's part. Rajan starts studying surgery and dedicates himself to the task of atoning for his childhood negligence by restoring Shanti's eyesight.
One day, in a fit of rage, Rai Saheb Deen Dayal kills a man with his gun and, like a good Samaritan, Ramdas takes the blame upon himself in order to shield a man so important and necessary to the life of the community. Ramdas goes to jail, leaving his wife and daughter to the mercy and in the care of Rai Saheb Deen Dayal, whom he thinks to be his friend.
But this noble sacrifice finds no reciprocity in the heart of Rai Saheb and he and his gang not only do not look after the welfare of Shanti and her other but, indeed, succeed in driving the two women out of the town. Having arranged his son's marriage in a rich family, Deendayal was anxious in any case to sever the growing ties of affection between Shanti and his son Rajan.
When Rajan comes back to the town he finds Shanti gone. His inquirie elicit only evading replies from his father. But his succeeds in locating the missing women and Shanti gets back her eyesight just in time to receive her father, Ramdas, back in their home upon his release from jail.
After his release, Ramdas discovers that the man whom he had always imagined to be an epitome of virtue and solid respectability is, in fact, a poisonous snake-a regular satan. He tumbles to many awful truths during his investigation of the affairs of the town.
Girding up his loins, at least, Ramdas launches a relentless crusade against Rai Saheb Deendayal and his gang of conspirators.
They decide to liquidate him. But, by one of those curious twists of fate which regulate our destiny, Rai Saheb's own son Rajan is stabbed instead.
This creates so much consternation in the evil doers camp that all of a sudden they all stand exposed in their true colours. Nemesis overtakes them and God emerges triumphant.
(From the official press booklet)