Kadak Singh is a crime suspense drama that centres around Kadak Singh aka A.K. Shrivastava (Pankaj Tripathi), an officer of the Department of Financial Crimes who is the key to the case of a chit fund scam, meets with an accident and lands up in the hospital where he is diagnosed with retrograde amnesia. Despite being a patient of retrograde amnesia, he listens to different versions of his life from different people regarding who he was and how he came to the hospital. As he tries to separate fact from fiction, he also finds out the reason behind his condition and who is behind the chit fund scam.