মার্কিন সরকারের অতন্দ্র-প্রহরা ভেদ করে দ্বিতীয় বিশ্বযুদ্ধ শেষে জনৈক বৈজ্ঞানিক একক প্রচেষ্টায় একটি গোপন তথ্য রাশিয়ায় পাচার করেন। মানব-সভ্যতার ইতিহাসে আর্থিক মূল্যমানের দিক থেকে এটাই নাকি সবচেয়ে বড় জাতের বিশ্বাসঘাতকতা। 'কী, কেন; কীভাবে ও কে?' সেটাই 'বিশ্বাসঘাতক'-এর মূল উপজীব্য।

Narayan Sanyal (bn: নারায়ণ সান্যাল) was a well-known & versatile writer of modern Bengali literature. He received several awards for literature including Rabindra Puraskar (for Aporupa Ajanta in 1969), Bankim Puraskar (for Rupmanjari in 2000), and Narasingha Dutta Award. Many of his books were filmed and he won the Best Film Story Writer Award (for Satyakaam) by Bengal Film Journalists.

Sanyal wrote numerous books that dealt with many topics, such as children, science, art and architecture, travels, psychiatry, technology, refugee problems, history, biographical pieces, encyclopedia of animals, social novel and Devadasi-related. He also wrote a series of detective fiction called the Kanta (Thorn) series, the framework of which was borrowed from the Perry Mason series of novels by Erle Stanley Gardner. Some of the stories were inspired from popular Agatha Christie novels like Mousetrap, ABC Murders, etc.

Interestingly, this talented author also preferred writing books on deep shadow of many world famous works. One of the most popular Sci-Fictions 'Nakshatraloker Debatatma,' is based on the transformation of human race from primitive creature to civilized intelligent species controlling the whole earth. Then it deals with Jupiter exploration and a super intelligent Computer HAL. The three parted book is a clear shadow of 2001: A Space Odyssey by Arthur C. Clarke. In his book, NS renamed HAL as 'Jantra-Na.' In his mother tongue Bengali, it means 'Not a Machine'.

His most popular work is 'Biswasghatak' written about the Manhattan project that developed the first US Atom Bomb. This book is based on the shadow of Brighter than a Thousand Suns: A Personal History of the Atomic Scientists (1970), by Austrian Robert Jungk. Not a shadow, but almost translation in some parts. Few of the illustrations in this book have been taken from few Russian school level books.

Another book 'Timi Timingil' is on Whales. This stands on an article published in Readers Digest. But while NS accepted this for Timi Timingil, he never mentioned or thanked authors of 2001 or Brighter.

Most of the "Kanta" series stories were copied or heavily inspired from Perry Mason novels. For example, "Ristedar-er Kanta" was copied from The case of the beautiful beggar, "Abhipurbak Ni-Dhatu Au-er Kanta" was inspired from The case of the restless redhead. Some of the stories were inspired from Agatha Christie stories. For example, "Dress Rehearsal-er Kanta" was inspired from Three Act Tragedy. NS acknowledged his inspirations in his first few "Kanta" series books, but forgot to do so for the latter ones.

Thousands of NS fans feel sorry of this as a man of his talent could have developed something even better instead of just 'Copying' and retouching others works while he had indeed produced some excellent works himself.

But it is undoubtedly accepted by all that NS was one of the finest authors in Bengali and he was a class apart from the flock of contemporary Bengali writers those who too dependent on sentiment and emotional overdose in their writings and too dependent on monopolist Bengali media/publication groups in commercial front.