The movie starts in 1995, when China had already completed 43 nuclear tests while India was still at 1 peaceful nuclear test in 1974 and is under immense pressure from other nuclear countries and rival neighbours Pakistan and China. The Prime Minister's Office meets and discusses alternatives to deal with the power show by China. Ashwath Raina (John Abraham), an engineer, suggests a plan to perform a retaliatory nuclear test but is ridiculed by the present ministers. Suresh Yadav, the PMO Secretary, later asks Ashwath to prepare a file on his plan but asks him to keep it brief. Ashwath submits the file and also gives Yadav a floppy which contains the details of the file. Yadav submits a half-baked plan to the Prime Minister and ignores the contents of the floppy. A hasty decision is made to go ahead with the test and Ashwath is kept out of the mission. The plan fails after an American Lacrosse Satellite photographs the test preparations and the United States immediately respond by sternly warning not to continue with the tests. Looking for a scapegoat for his own negligence, Yadav blames and suspends Ashwath.

Three years later a new Prime Minister is sworn in. Ashwath now lives in Mussoorie teaching IAS aspirants. He gets an offer to teach at Delhi University, which was set up by the new PMO Secretary to investigate the failure in 1995. He gives him an opportunity to explain his actual plan which involved keeping the whole operation secret from the USA and operating the installation in Pokhran at satellite blind spots. He is asked to gather a team and work on the nuclear test setup. The whole mission is to be kept confidential.

The team proceeds to start with the nuclear test setup in Pokhran. The surge of activity alerts spies from US and Pakistan, who are now trying to find out the reason behind the activity. After facing several challenges, the team is able to have a successful test, which establishes the country as a new superpower not to be taken lightly.

• John Abraham as Ashwat Raina
• Diana Penty as Ambalika Bandyopadhyay
• Boman Irani as Himanshu Shukla, Principal Secretary to the Prime Minister
• Aditya Hitkari as Dr. Viraf Wadia
• Vikas Kumar as Major Prem Singh
• Yogendra Tiku as Dr. Naresh Sinha
• Ajay Shankar as Puru Ranganathan
• Anuja Sathe as Sushma Raina, Ashwat's Wife
• Darshan Pandya as Pakistani Spy
• Zachary Coffin as Stephen
• Mark Bennington as Daniel
• Satinder Singh Gahlot as Suresh Yadav The Former Principal Secretary to the Prime Minister
• Praveena Deshpande as Ashwat's mother.

Parmanu was officially announced on 15 April 2017 via Taran Adarsh's Twitter handle. John Abraham was approached by film producers Prerna Arora and Arjun N Kapoor with the script, which was further developed. Parmanu was shot in Delhi and Mumbai, with major portions being shot in Pokhran, and areas of Pokhran Fort, Aada Bazaar, Gandhi Chowk Main Market and the Gomat Railway Station. The principal photography of the film began on 31 May 2017 and the shoot was completed in August. About the film, Abraham said: "Parmanu is an ode to the Army and scientists, who although ordinary people, truly accomplished extraordinary feats in the face of adversity to ensure that India finds its due place on the world nuclear map."

The first look of the film was revealed by Abraham through his Twitter handle on 22 June 2017. It showed his face merged with the map of Pokhran.^[20] The second poster of the film was released on 14 August 2017 which showed Abraham running with jeeps, bunkers in the background.^[21] Two posters of the film showing John and Diana in Army uniform were released on 3 November 2017.^[22] Teaser of this film was released on April 5th 2018. The trailer was released on 11 May 2018.^[23]

Earlier scheduled to release on 8 December 2017, the film released on 25 May 2018 across 1935 screens.^[24][25]

The music of the film is composed by Sachin-Jigar and Jeet Gannguli while lyrics are penned by Vayu, Rashmi Virag, Sachin Sanghvi and Kumar Vishwas . The songs featured in the film are sung by Arijit Singh, Divya Kumar, Yasser Desai, Keerthi Sagathia and Jyotica Tangri. The first song of the film titled as Shubh Din which is sung by Sagathia and Tangri was released on 14 May 2018. The album was released by Zee Music Company on 15 May 2018.

Vipin Nair of The Hindu gave the soundtrack 2.5/5 stating that the soundtrack is a "middling start to the year" for the composer duo.^[27][28]