After years of watching bad copies of this on cable channels at 2am, I finally tracked down the DVD. It was worth the wait. I couldn't understand it back when I was 13 in the 1970's and I still can't understand it now. But it is absolutely brilliant. Moore is at his best - before Brett Sinclair and before James Bond - he is absolutely at the top of his game here. The mental unravelling is amazing to watch. The final meeting with the doppleganger is both claustrophobic and nightmarish. The driving scene at the end has shades of 2001 mixed with Dali. This was the end of the sixties after all. I really love Roger Moore, especially the Persuaders, the Bond films and the Wild Geese. He made some of the best stuff of my childhood. Perhaps this is the best one.