Back in 2016, when Indian Solicitor General Ranjit Kumar announced that India would not seek the return of the Kohinoor, the most prized jewel to have escaped our shores as a gift to the British royalty, filmmaker Rensil D'Silva was busy writing a story, which stemmed from a not-so-very-innocent premise: What if someone was to steal it?

The thought stayed with the director of Saif Ali Khan-starrer Kurbaan for years, spurred initially by a visit to the iconic Tower of London, a guarded fortress, where the Kohinoor was on display. "I started researching about the castle, its terrain and the security," he says. He discovered that it was the most guarded place in the world. He says the walls of the jewel room are made of a steel alloy and can resist a nuclear attack. And the elite British commandos are on 24/7 duty.