Chilling documentary lifts the lid on cold case of a 19-year-old woman who was sexually assaulted and brutally bludgeoned to death in her boyfriend's Texas home... as heinous crime still remains unsolved 16 YEARS on

Brittany McGlone, 19, was brutally attacked in her sleep at the house in Winnsboro, Texas, in 2007. Here, FEMAIL has laid bare the disturbing realities of the unsolved case.