Role model. Icon. Space scientist. Missile man. Bestselling author of books that have sold in millions and been translated into every Indian language. Bharat Ratna. Besides Padma Bhushan and Padma Vibhushan. A following of millions. Dozens of other honours. The most popular President ever.

In the small, exclusive world of New Delhi's power centres, however, all that can count for little with the bureaucrats who set the rules and the politicians to whom they report. In Kalam: The Untold Story, R K Prasad, his private secretary from 1995 to his death in 2015, shows us another Kalam-accomplished, successful, always modest despite the high positions he occupied, as also vulnerable and innocent. It is a journey he was part of, from Kalam's time as Scientific Adviser to the Defence Minister and DRDO chief, through Principal Scientific Adviser and President, and the years after the presidency. It throws new light on his relationship with political leaders, including those at the highest level, and the truth behind some of the controversies. Most of all it shows Kalam at his best, facing adversity and disappointment in a way that explains why he was what he was-an extraordinary man.