he modeled several portrayals of the cops based on his own observations. mehta said that the making of the series was a "personally transformative journey" for him. he spoke to several police personnel involved in the case and tried "retracing the paths that the police took during the course of the investigation." it took mehta six years to finish his research. the series was shot in delhi over the course of 62 days. mehta initially wanted to make it as a feature film, but as he continued the research, he realised that he could not fit the content in that length. the character of vartika was based on chhaya sharma, the former deputy commissioner of police in delhi.