Delhi Mein K. D. Giraftaar Part 1

K.D. Pathak's childhood friend, Neeraj Marwa, informs him that his wife, Renuka, has been arrested on charges of medical negligence for the death of a patient. Subsequently, Neeraj is murdered, and K.D. Pathak finds himself detained by the Delhi police. How will K.D. Pathak go about demonstrating his innocence?