Rocketry: The Nambi Effect

Work on the project was first reported by Madhavan in the media during April 2017, when he announced that he was set to appear in a biopic featuring the "extraordinary story of an unsung hero", who was "neither an actor nor a sportsman". He called the project his "biggest film ever" and stated that he had worked silently on the script of the film for a period of two years after becoming intrigued by hearing the tale of the former Indian Space Research Organisation (ISRO) scientist Nambi Narayanan's false espionage charge.[3] To develop the script and to provide a more factual account of the events, Madhavan regularly met with Narayanan, garnering his approval for the film and discussing the scientist's life experiences. As a result of their conversations, Madhavan chose to alter his original script to include portions from Narayanan's entire career and his services to the Indian space programme, rather than just matters related to his 1994 arrest.[4][5] For the script, he also took inspiration from Narayanan's autobiography Ormakalude Bhramanapadham (2017) and Arun Ram's official biography of the scientist titled Ready To Fire: How India and I Survived the ISRO Spy Case (2018).[6]

In October 2017, Madhavan confirmed that pre-production work for the film was underway and that he would portray Narayanan from the ages of 27 to 75, and that he was gaining weight to film the scenes featuring the older version of Narayanan first, after taking advice from Aamir Khan. Madhavan also announced that alongside his screenwriting and acting credits, he would also be one of the producers of the project.[7]

In late 2017, Madhavan held discussions with the likes of S. S. Rajamouli to be the film's director, before confirming Anant Mahadevan, who had previously directed Madhavan in the Hindi television serial Ghar Jamai (1997) and the romantic drama film, Dil Vil Pyar Vyar (2002).[8][9] In regard to making of the film, Anant Mahadevan stated that he hoped to differ in the script in comparison to other biographical films, and suggested that he would not call the film a "biopic" but an "incisive investigation into a brilliant mind and India's ambitious space technology".[10] He also added that he felt that Madhavan was the "only Indian actor qualified to do this part" owing to his background as an electronic engineer with air-force training, and because he was "a thinking-actor who is also well-read".[10] The title of the film Rocketry: The Nambi Effect and a teaser for the film was unveiled in late October 2018, with Madhavan also announced as a joint director of the film. A launch event also coincided with the teaser release, with Madhavan, Anant Mahadevan and Nambi Narayanan in attendance.[1]

Principal photography began in January 2019, and was shot as a trilingual, being filmed simultaneously in English, Hindi, and Tamil.[10][11] A few days after the start of the shoot, Anant Mahadevan left the project and Madhavan took over as the project's sole director.[12] Scenes featuring Madhavan as the aged Nambi Narayanan were filmed first, with the actor taking up to 14 hours to get into the look following extensive make-up.[13][14] During the first schedule in India, Simran joined the film's cast to portray the wife of the lead character, while actors Suriya and Shahrukh Khan agreed to make cameo appearances in the Tamil and Hindi versions respectively as themselves.[15][16] Other actors who joined the cast during the production were Tamil actor Jagan to portray a scientist, Rajit Kapur to feature as Indian physicist Vikram Sarabhai in the Hindi and English versions and Ravi Raghavendra as Vikram Sarabhai in the Tamil version.[17]

In late January 2019, the team moved to film scenes in Georgia and Russia. The team completed the shoot five days prior to the schedule, despite shooting in unfavourable weather conditions.[18][19] In April and May 2019, the team shot scenes in India, with Madhavan shaving his beard to play a younger version of the character. The team subsequently moved on to film the final schedule in France and Serbia.[20][21] Production was completed in Serbia during June 2019, with Scottish actors Ron Donachie and Phyllis Logan also a part of the final schedule.[22][23] Post-production began in July 2019, with music composer Sam C. S. completing the background score by mid-October 2019.[24]