Worthy of Sherlock Holmes for its perplexing weirdness is a perennial head scratcher in Tucson that has stumped residents with a 35-year trail of bizarre clues.

What is the May Day mystery?

No, I have to admit, it's my favourite mystery.

And I first came across it probably about 10 years ago.

When I was writing about the smiley face killers and doing all my research for that initially,

I came across this organisation and at first I thought, oh my goodness, that's maybe linked

and that's what led me down the rabbit hole.

It's so difficult to understand.

You've really got to be a member of Mensa, I think, to be able to try and work out what's

behind the May Day mystery.

And I think it would probably fascinate

you. But be warned, you can spend hour upon hour, day upon day, trying to work out and decipher

and decrypt what it is that they post because the messages are so mysteriously difficult to

understand. And they incorporate art, culture,

ancient history, and certainly religion. And I would suggest you probably have to have PhDs

in a lot of these fields of study. And yet, you know, sometimes someone with the right kind of

insight may be able to crack it without any of those necessary.

Certainly the people behind it are very intellectual.

And at first when I was looking into it, I thought it was such a sinister, terrifying organisation.

Or is it really about life after death? I may have got that completely

wrong, probably have, maybe it was to do with all the really disturbing topic matters that I was

having to research. There's still some of it that unnerves me, particularly when it comes to the messages from what they call themselves the freaks.

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