Makers of the fourth installment of the horror-comedy franchise Aranmanai have launched the trailer of the film.

The trailer video follows deaths of Sundar C role's sister (Tamannaah) and brother-in-law (Santhosh Pratap). The lead is perplexed when he learns his sister and brother-in-law were spotted elsewhere when their mortal corpse were found. Upon discovering that a demon called 'Baak' has possessed their souls, he goes on a mission to rescue them.

Talking about the plotline without elaborating much at the trailer launch event in Chennai's Leela Palace hotel, director-actor Sundar C said he heard of an Assamese folklore about Baak, a water demon, which, according to legends, were one of the many reasons why even flourishing empires couldn't spread beyond Brahmaputra River.

He added that he doesn't cash in on the previous hits. "I begin process of a sequel only when I have an interesting story to tell. The stories and descriptions of the Baak demon helped me in finalising the screenplay," said Sundar C.

Apart from Santhosh Prathap, Sundar C and Tamannaah, the film also stars Kovai Sarala, VTV Ganesh, Rajaendran, Singapuli and Yogi Babu.

Aranmanai 4 is backed by Benz Media Pvt Ltd and Avni Cinemax (P) Ltd. The technical crew of the film includes Hiphop Tamizha scoring the music with Esakki Krishnasamy as cinematographer. Fenny Oliver S is the editor.