The pervasiveness of social media has resulted in increased public involvement in key discussions about social issues, as well as creating greater affordances for individual expression and collective mobilisation. In December 2012, the rape and murder of a 23-year-old Indian student in New Delhi, India, was followed by widespread condemnation and public action organised and coordinated through social media. In March 2015, a controversial BBC (British Broadcasting Corporation) documentary, “India’s Daughter”, about the incident was broadcast despite restrictions imposed by the Indian Government. This paper explores the interplay between Mainstream Media ("Fourth Estate") and Social Media ("Fifth Estate") through a case study analysis using computational techniques to analyse 250,000 tweets collated following the broadcast of the documentary. The primary contribution of the paper is a contextualisation of our findings and analysis within the theoretical frameworks of social movement theory and postcolonialism in order to understand the interactions between mainstream media and social media. Limitations and issues around implications for conducting inter-disciplinary social media research are also discussed