The following story of the appearance of Lord Nrisimhadeva is from Srimad-Bhagavatam, Canto 7, Chapters 2-10.
At the performance of the Rajasuya sacrifice by Maharaja Yudhisthira, the celestial sage Narada Muni appeared to give spiritual instructions to the Pandavas.
The author, Dr. Aravinda Rao is a retired police officer who has been a teacher and writer on Vedanta after his retirement. He is also an observer of the global forces and their assaults on India on several fronts. The arguments in the present book include Vedanta alongside sociological observations.