Nayanthara's O2, set inside a bus, will stream on Disney+Hotstar from June 17

Over 70 per cent of the scenes in Nayanthara-starrer, O2, directed by newbie GS Viknesh (former assistant to Venkat Prabhu), are said to have been filmed inside a bus. This much-awaited upcoming thriller will have a worldwide premiere on June 17 on Disney+Hotstar.

After an accident, a mother and her eight-year-old son become trapped inside a bus. As a result of a chronic lung disorder, the kid must use an oxygen cylinder to survive. Similarly, trapped inside the bus, a cop also tries to get his hands on the oxygen cylinder to survive. A mother's decision to save her son and deal with the situation is at the heart of this story.

Travel is an important element in O2, says Viknesh. When asked if the film discusses environmental issues, he admits it does touch upon the idea and throws light on the significance of mother earth. According to reports, Dream Warrior Pictures decided to bankroll O2 only after listening to the complete narration as they felt it had a fresh and unique story premise.

Viknesh was not a huge fan of plants at the time he started writing O2. But by the time he was done with the filming process, gradually, the number of plants at home increased. “Now, I have 200 to 300 varieties of plants,” he says. Such was the impact of the film. The writing process changed his mind drastically, towards a lot of pertinent issues, admits Viknesh. “I hope O2 brings about some awareness and understanding of how we need to interact with nature,” he adds.

There is an element of heroism in the film, which Viknesh felt Nayanthara could pull off with ease. O2 went on floors in July 2021 and was completed in four schedules that same year.

With music by Vishal Chandrasekhar, the film's editing will be done by Sarpatta Parambarai-fame Selva RK. Thamizh A Azhagan, who recently shot Manmatha Leelai, is the cinematographer of O2.

Others in the star cast include late actor RNR Manohar, Leena, Aadukalam Murugadoss and Jaffer Idukki, among others. Set against the backdrops of hill regions that connect Tamil Nadu and Kerala, O2 has Nayanthara playing Parvathy, and Rithvik will be seen as her eight-year-old son.