Eighteen months after Chinese student Lin Jun was brutally killed and dismembered, a group of Internet users was attempting to track down Luka Rocco Magnotta, whom they also linked to videos on the web showing kittens being slowly suffocated in agony. In this documentary, we meet these passionate trackers and witness a re-enactment of their Magnotta investigation. See how they carefully studied the videos to determine that the first kittens had been killed in Toronto, and how Magnotta – who had chosen the Internet as his medium of choice to indulge his obsessive hunger for fame – had undoubtedly put the trackers back on his tail, even going so far as to contact them himself. They believe that if police had taken their fears and investigation more seriously, Lin Jun might still be alive today. In a series of exclusive interviews, these cyber vigilantes tell the story of their manhunt, drawing us into the twisted world of the murderer they were after.