Andha Naal

Usha is Rajan's wife who mourns his death and bears the weight of his dangerous secrets. She discovers Rajan's affair with Ambujam and tries to reform him, but cannot change his path. In a moment of desperation, she attempts to shoot him, but the gun fires accidentally, leading to his death. Her actions become a focal point in the investigation and a test of her loyalty and sanity.

Rajan is a brilliant radio engineer with a dream to provide affordable radios to the poor. His career takes a dangerous turn as he becomes a spy who sells India's secrets to Japan. His extramarital affair with Ambujam and his reckless attitude toward the pregnancy add personal motivations that complicate the case.

Chinnaiah Pillai is Rajan's neighbor who appears concerned about the family and property but hints at deeper resentments. He recalls a confrontation where Pattabi demanded his share of the estate. His testimony frames Pattabi as a suspect and pushes the investigation toward family dynamics.

C. I. D Sivanandam is a probing and methodical detective who joins Naidu to solve the murder. He uses psychological exercises and fingerprint analysis to separate truth from illusion. His investigation ultimately uncovers the true motive behind the death while revealing deeper motives.

Pattabi is Rajan's younger brother who resents the family tension over property. He recounts a bitter confrontation over the estate and expresses remorse for his failings as a brother. He denies intent to kill, though his behavior fuels suspicion and tensions within the family.

Ambujam is a dancer involved in an extramarital relationship with Rajan and is pregnant with his child. She asserts that Chinnaiya is her foster father and that their meeting originated during a picnic. Her position as Rajan's mistress makes her a suspect and a key to understanding Rajan's motives.

Hema is Pattabi's wife, caught in the property dispute that fuels tensions. Her anger at Rajan and a belief that the affair could destroy her family reflect the volatile emotions at play. She eventually reveals Rajan's extramarital relationship, intensifying the motive web.