We all have our ways of lumping and spliting the world: PC/Mac, crunchy/smooth, those who like Neil Young/those who don't and so on. My own version is brutally simple: the world is divided into those who have had dealings with a compulsive fantasist and those who have not.

Because once you have had to deal with such an individual, you will never take anyone at face value, ever again.

To be clear, I'm not talking about 'Why yes, that £100 hairdo really does suit you!' or 'Thanks, mum - I've really been looking forward to this new Susan Boyle CD!' type white lies. I mean a deliberately constructed false life. As with all lies, it grows and grows until more and more people twig that the details don't quite add up. And then it implodes under its own weight, leaving a trail of ill-feeling behind it.

Most of us, I think, find it hard to believe that anyone would do such a thing. I certainly did until my own encounter with a fantasist. No direct harm was done to me but, several years later, I still find it all quite chilling. I've come across a few since but not on the same scale, thank goodness.

By now, if you are still reading this, you will either be thinking 'Eh, WTF?' or nodding wearily. Hence my first para. If you're in the former camp, this song may help explain matters. If in the latter, you may agree with me that it is indeed the scariest song ever: