The Hindi detective novel Laal Panjha , written by Durga Prasad Khathri, and published in 1927, was translated to Malayalam by Mohan D. Kangazha and was titled Chemanna Kaipathi . Published in 1958, it was a bestseller and had several reprints. The story centred on a dacoit who threatened and blackmailed people by sending letters signed Chemanna Kaipathi (Red Palm) and then executing the crime.

The resemblance between the Malayalam filmKarutha Kai , released on August 14, 1964, and this novel was much talked about at that time. The main character in the novel and the film who commit the crime leave their signature asChemanna Kaipathi in the novel, and Karutha Kai (Black Hand) in the film.
The title cards and song book of the film credit the story and dialogues to Sree. It was usual for writers to use pseudonyms but in this case it is not a person but perhaps a pseudonym for the story department of the production house. Directed by M. Krishnan Nair, the film had cinematography by M. Kannappan, editing by N. Gopalakrishnan, dances choreographed by E. Madhavan and music by M.S. Baburaj.
Prem Nazir, Thikkurissi Sukumaran Nair, Jose Prakash, Paravoor Bharathan, Adoor Bhasi, S.P. Pillai, Sheela, Shanthi and others were cast in important roles.

The coastal town of Parakkoottam is terrorised by a gang of dacoits. The leader who goes by his signature Karutha Kai executes his plans through his faithful assistant Vijayan (Kundara Bhasi). He is only person who knows the real identity of their leader. The Government appoints Bhasu (Prem Nazir), Inspector of Crime Branch to investigate into the murder of a coast guard. Bhasu comes to the town in the disguise of an artist. Here, Bhasu meets his college mate Latha (Sheela). She introduces Bhasu to her father Thampi (Thikkurissi Sukumaran Nair), a respectable person who works for the welfare of the society. Bhasu stays in the beach bungalow owned by Thampi and begins his investigation. Gradually, Latha is drawn towards Bhasu.

Radha (Shanthi), daughter of the murdered coast guard, joins hands with Bhasu in the investigation. Karutha Kai sends a letter to Madhava Menon (Jose Prakash) demanding Rs. 5,000 failing which his daughter would be kidnapped. Menon seeks the help of Thampi who advises him not to give the money. Thampi announces reward of Rs. 10,000 to anyone who helps to bring Karutha Kai before law. Two private detectives, Damu (S.P. Pillai) and Soman (Adoor Bhasi) take charge of the security of Menon’s house. But Karutha Kai kidnaps Menon’s daughter (Baby Vinodini). Menon sends the ransom amount to the place specified by Karutha Kai. Bhasu reaches the spot and follows Karutha Kai’s men and manages to locate their hideout, a lodge in the town. Radha, feigning to be speech impaired, finds a job in this lodge. Here she takes care of Menon’s daughter now under custody of the dacoits. Bhasu, Damu and Soman enter the lodge disguised as dancers. Radha escapes with Menon’s daughter while the dacoits were engrossed in the dance performed by Bhasu and his group. The manager of the lodge is arrested by the police, but he is murdered on the way to police station by Karutha Kai.

Now, Thampi gets a threatening letter from Karutha Kai with a demand of Rs. 10,000. Thampi seeks the support of the police. Vikraman and Kader (Paravoor Bharathan), members of the dacoit gang lose faith in their leader whom they have never met and decide to stake a claim in the booty. They move towards the hideout followed by Bhasu.

In the climax scene the identity of Karutha Kai is revealed. Everyone is stunned to find that it was Thampi who was heading this gang. He was clever enough to send a letter to himself in order to divert the attention of the police. In a desperate attempt to escape Thampi shoots down Vikraman and Kader. In the ensuing fight between the police and Karutha Kai’s men, Latha is killed. Thampi is arrested. Bhasu leaves the town after a successful mission.

The songs penned by Thirunainarkurichi Madhavan Nair and set to music by Baburaj like Panchavarna thattha pole …(K.J. Yesudas, Kamukara Purushothaman and chorus) which is considered the first song in Malayalam cinema composed in the Qawwali style, Kannukal kannukal daivam nalkiya …(Kamukara-L.R. Easwari), Ezhu nirangalil ninnude …(Kamukara-S. Janaki), Paalappoovin parimalamekum … (Janaki) and Manathe penne … (P. Leela) became very popular.
Will be remembered : As a successful crime thriller, for its music, especially for the songPanchavarna thatha pole …