The plot starts with the protagonist in a coma and on life support. The film, from the beginning, tells two stories of the same person, one in colour and the other in black and white.

A detective from the Mumbai crime branch starts investigating the incident that caused the protagonist's (Siddharth) current state. The Detective, going through his belongings, stumbles upon some scribbled notes and a mysterious pill. Meanwhile, police capture two suspects and interrogate them for information.

The story starts with Vicky who is from a village and working as an Usher in a movie theatre owned by Durai (Aadukalam Naren). Vicky suffers from insomnia. On one of his sleepless nights, Vicky is contacted by a drug dealer who gives him Lucia pills as a solution to his insomnia. This drug is said to have the capability to help one dream the life they want but has the side-effect, that upon discontinuation the same dreams shall turn into nightmares.

With the help of the Lucia pills, Vicky starts seeing himself as a successful actor called Vignesh surrounded by people he knows in the real world. Film actor, Vignesh's life is depicted in black-and-white. Durai, the theater owner where Vicky works, had directed a film in his youth produced by a thug, who now wants Durai to sign off his theatre for his debt. In the black-and-white life, Vignesh and Durai get a number of death threats from a person. More events from the dream are followed by similar events in reality as Vicky falls in love with Divya (Deepa Sannidhi) who is a model in the dream and a waitress in reality.

In the dream, Vignesh and Divya hit it off easily at the beginning but later friction arises when Vignesh expresses his discontent with Divya working in the film industry. Meanwhile, in reality, Vicky struggles to win Divya's heart, who rejects him first due to his low salary and falls later for his humble character. Divya's attempts to get Vicky educated and lead him to get a better-paying job turn out to be futile and result in the death of Durai at the hands of goons. Frustrated, Vicky chooses to leave Divya and continue to work in the theatre, despite the threats. Vicky and his foreign friends redecorate the theatre and release Durai's film. He later reconciles with Divya, who agrees to marry him.

In the dream, Durai is kidnapped, and Vignesh rescues him with the help of police. In the process, all of the goons are either arrested or killed except for the contract killer. Vignesh feels Durai is not safe with him and decides to fire him. Vignesh breaks up with Divya and sends away his entourage so as to be alone. Later, a visually disturbed Vignesh finds himself in a trashed room. Vignesh gets hold of the torch and through its light sees the "torch-shiner" Vicky inspecting the screen of the theatre.

Divya misses Vignesh and tries to get back with him but Vignesh is in his own shell and shuts out everyone from his life. Divya receives an unexpected call from Vignesh some days later and he asks her to meet him. He tells her that he cannot decide if the present moment is a dream or reality but he is ultimately happy. He says that he should not confuse his dreams and real life. Asking Divya to close her eyes, Vignesh jumps off the roof to the disbelief of everyone present, including the contract killer waiting to kill him.

In the present, the detective with the help of the suspects performs a sting operation on the drug dealer and learns more about the Lucia pills. Meanwhile, Divya is caught in an attempt to kill Vignesh by taking him off life support. During her interrogation, the whole investigating team along with Divya watches a re-run of an interview of the film star Vignesh. In the interview, Vignesh expresses his dissatisfaction with stardom and reveals that he is actually color blind from an accident in his childhood. He tells the interviewer that he dreams of being a normal person and in fact, in one of his dreams he is a "torch-shiner" who gets no attention from people and is happily in love with the dream of his life.

The detective is now convinced that Vignesh is living in his own version of reality and chose to be in his dream over the real world by attempting suicide. Divya cries near a comatose Vignesh in the hospital and simultaneously Vicky is shown happily married to Divya and have a daughter. Vignesh's health begins to deteriorate and the doctors attempt to defibrillate him. Simultaneously, Vicky, aware and alive in his dream finds everything disappearing around him and is killed by a shot to the head. Vignesh wakes up from his coma to see the astonished doctors and Divya and Durai's relieved faces, implying that it was actor Vignesh who was real, and Vicky was his illusion