Imagine this... You find a file on your hard drive claiming that hackers have taken over your PC and encrypted your files. The hackers demand money in exchange for providing the means to recover your data. You think it's a scam, a hoax - but then you find that your precious personal data is in fact encrypted. Personal documents that you urgently require for work or for your studies are now inaccessible to you. You have no backup. What do you do?

It sounds like the plot for some kind of lame movie, but in fact this is just what happened to Helen Barrow, a 40-year-old nurse from Rochdale in the UK. She is believed to be one of the first victims of the con in the UK, where hackers hijack computer files and blackmail owners to get them back.

In this case, the demands on Helen where that she buy drugs from an online pharmacy in order to get her data back, but the demands could be for anything. This practice, known as Ransomware, may be set to explode.

"When I realised what had happened, I just felt sick to the core. I was in shock. It was a horrible feeling and I thought I was going to lose all of my work. I had lots of family photographs and personal letters on the computer and to think that other people could have been looking at them was awful."