Nagesh alias Naga is an honest yet unsuccessful real estate broker who lives with his mother, younger brother, and sister, Lakshmi, who is deaf and mute. Naga meets a girl named Himaja, and they fall in love. Things go fine for Naga and his family until there comes a situation where he has to sell his ancestral property - a dilapidated movie theater - to conduct Lakshmi's wedding. Naga and his friend Kaala travel to another town to sell the theater. Due to a small accommodation problem, they end up spending the night at the theater itself.

Over the next few days of their stay, both Naga and Kaala experience several paranormal activities around them, and all their attempts to bring prospective buyers go futile. Naga also starts having weird dreams every night in which random people are murdered. He then wakes up to the news to find that those people are dead in real life. Confused and frustrated, he seeks help from different godmen to find out what is wrong, but nothing works out. Meanwhile, a local politician realises that the people being murdered mysteriously are none other than his henchmen and his close associates. He finds that there is something abnormal about all these murders and consults with a Nambudiri, who tells that a malevolent spirit from the theater is causing all this mayhem and that they have to perform an exorcism. Paranormal occurrences keep happening around Naga, and he discovers that the spirit tries to take him to a well inside the premises. Himaja also tells him about her own paranormal vision of a murder and how she felt an apparition near her while she was on video chat with Naga and he had slept off. She is not able to positively identify, since she had closed her eyes out of fear, but since Naga had recorded the video chat, he watches it, only to find that it was he who appeared in the video and realizes that he is the one behind all those murders and hence the dreams. Naga soon prepares himself to face the spirit directly and asks for answers when the spirit reveals itself to be a woman and an old acquaintance to Naga.

Tamilselvi is a social activist who is popular on Facebook for her brutally honest articles about the wrongdoings in the society. She lives with Dr. Shakunthala, who runs a small orphanage with a few children and provides free medical services to the underprivileged. Naga was the real estate broker who helped them find a house. It so happens that a bigger orphanage lends a helping hand to Shakunthala, with the promise of taking a few kids from her orphanage and providing better education and a future. She and Tamilselvi entrust an early teen girl to them and send her off but soon receive a call from her that she and many other children have been kept hostage in a bungalow. Tamilselvi gets a ride from Naga and sets out to investigate and rescue the kids. She is horrified to find that the politician is making a deal with a foreign corporate company for exporting unlimited human blood for them to extract the blood plasma and use it for various cosmetic purposes, thereby commercializing it. The politician is making use of the orphan children's blood to achieve this target, and the local police officer is his aide. The girl from Shakunthala's orphanage is raped by the police officer, all of her blood is drawn by doctors for the plasma, and she is then killed. Tamilselvi records all of this and tries to escape with Naga's help. Naga is oblivious to all the danger that she might be in and just drops her home, but she is captured and attacked by the politician's henchmen at the abandoned theater and is thrown into the well when she is still alive and is left there to die.

All the evidences that Tamilselvi collected for Facebook are destroyed, and Shakunthala is killed. Tamilselvi's spirit has been waiting for revenge since then, and when she realizes that Naga is back in the theater, she makes use of his tiny paper cut wound to possess him through blood contact, and that is how she had murdered all those men who helped the politician. Meanwhile, the politician and the Nambudiri perform an exorcism at the theater, and it is here that Naga is dismayed to learn that his brother is also a part of the politician's team as a doctor that draws all the blood. A fight ensues, and a possessed Naga tries to kill his brother and the politician but is subdued by the Nambudiri's mantras. Tamilselvi is enraged and ultimately uses blood contact again with Naga's brother's bleeding wound and possesses him instead. She makes him kill the politician and himself. Now that she is avenged, Tamiselvi's spirit leaves the theater. Naga and his family are finally able to live in peace.