Many years ago in a cheap hotel in Bangkok I noticed the table lamp had a join in its figure 8 flex. I thought, "That looks a bit dodgy", and picked up the flex (after the join). Suddenly the room light went out followed by the flex glowing red hot below the join until it melted. Room light came back on and room full of acrid smoke.
Using my trusty neon screwdriver I carried I was able to remake the now somewhat shorter lead.