Several mysterious symbols have been sent to us from around the world, and after a bit of investigation by some of our expert referees, we've managed to find some plausible explanation for most.
But there are a few which haven't been met with a satisfactory explanation - hence this series. If you have any ideas about any of the symbols below, please let us know.
...and of course, any of these symbols could have no meaning at all - merely the results of somebody's doodling. But if you fancy a challenge, click on a link above for more details.
Happy sleuthing!