Director: Mahesh, N. Shivankutty Nair; Writer: Sree; Producer: P. Subramaniam; Cinematographer: E.N.C. Nair; Editor: N. Gopalakrishnan; Cast: Madhu, T.K. Balachandran, Vaikkom Mani, Govindan Kutti, S.P. Pillai, Muthukulam , Muttathara Soman, Ramachandran, Shivan, Radhakrishnan, Shanthi, Rajasree, Rajeswari, Sarasamma
Duration: 01:46:00; Aspect Ratio: 1.333:1; Hue: 107.303; Saturation: 0.017; Lightness: 0.334; Volume: 0.371; Cuts per Minute: 9.207
Summary: Santhan, a medical practitioner, is in love with his uncle's daughter Vimala; their marriage is fixed. Vimala's father was a banker who died under mysterious circumstances. Santhan develops a medicine, which turns a person into a monster when consumed. He also invents the formula that reverts the person back to their original self. Santhan keeps this invention a secret. From his uncle's diary, Santhan learns that other greedy directors of the bank are responsible for his death. Santhan decides to take revenge on them by utilising his invention.
Vimala's cousin Mohan is in love with Vilasini, a night club dancer. The other directors of the bank influence Mohan, through Vilasini, and attempt to steal the bank documents from Vimala’s house. The monster appears before Vilasini and threatens her that she will be killed if she acts accordingly. Vilasini discovers the secret that it is Santhan who kills the directors of the bank. Mohan also learns about the secret that Santhan is the monster.
Vimala’s uncle Kochammavan comes to the city to conduct the marriage of Vimala and Santhan. The police also arrive there in pursuit of the monster. Mohan reaches the spot and exposes Santhan, who then changes himself into a monster. But before the police can arrest Santhan, he commits suicide.