Kaun? Who Did it? S01 E02 The Half Burnt Corpse

Dr. Chopra is found to be half burnt and dead in her apartment, just a few hours before her planned flight to the US. While sharing details of the case, Malini finds Adi absent-minded and glued to his game of chess. She throws a question that leaves Adi stunned - what led him to retire early from the force? A question that'll have to be answered, just as the question of who is the killer?