This program is an in depth investigation into new evidence that has been found surrounding the murder trial of O.J. Simpson. Who did kill OJ's ex-wife Nicole Brown Simpson and her friend Ronald Goldman? This is still a gripping tale. It may be five years on but this story hasn't lost its heady mixture of violence, race, sex and Hollywood glitz. Five years ago, the world watched spellbound as OJ Simpson was acquitted of murder. And interest in the case remains as great as ever. Why, asks the BBC's former Washington correspondent Bridget Kendall, are we still obsessed? Ask any American exactly where they were when the verdict in OJ Simpson's trial was announced and they will probably remember. It was one of those defining moments. When the dramatic announcement came that OJ had been found "not guilty", the reaction was almost as stunning as the unexpected verdict. America was divided down the middle. Five years since that moment, and still the ghosts in this weird and ghastly double murder have not been laid to rest. And it is somehow fitting that the latest investigation to unearth new clues into what might have happened - who did kill OJ's ex- wife Nicole Brown Simpson and her friend Ronald Goldman? - is not the result of police work, but a television documentary, OJ: The Untold Story. Once again, it is trial by television, a TV audience being invited to sift through the evidence and draw their own conclusions. What is more, there are some startling new revelations and a real-life American private eye to help guide us through the maze of new circumstantial evidence. Not exactly a suave Raymond Chandler hero with deadpan delivery, Bill Dear is no Humphrey Bogart. But as a tenacious private detective from Dallas, Texas, he certainly proves that all those American crime novels got one thing right: one private eye with a bee in his bonnet and apparently boundless energy can get a whole lot further in coming up with new leads than an American city police department. To begin with gruesome photos from the crime scene and eyewitness accounts from the LA police detectives reminds you of how they built their case, and convinces you all over again that surely the evidence against OJ was overwhelming. But then comes the analysis: the evidence that does not add up. Here the makers of this documentary have been careful not to be too categorical. They offer two sets of circumstantial evidence that point to two quite separate suspects and two quite different lines of inquiry. So who do they think did it? There is no final chapter to this new investigation. Watch it, and decide for yourself if you still think OJ is guilty.