For seven decades, speculation has persisted that the Somerton Man may have been a Soviet spy.
The mysterious figure whose body was found slumped on an Adelaide beach in December 1948 has never been identified, spawning theories ranging from espionage to affairs of the heart.
To lay the matter to rest once and for all, the South Australian government last year authorised an exhumation, and the Somerton Man's remains were taken from an Adelaide grave to a Forensic Science SA lab in the hope of harvesting DNA.
But little has been heard of the case since then.
"There is no update from Major Crime [Investigation Branch] on this case at this time," SA Police recently said.
As that work continues, Somerton Man researcher Professor Derek Abbott is persisting with his own parallel efforts.
Professor Abbott is a spy theory sceptic. While he concedes the possibility cannot be ruled out, his recent endeavours have focused far less on Russia than a country on the other side of Europe.
"It's very possible there's some Irish blood in there," Professor Abbott said of the Somerton Man's ancestry.
Red spies and Cold War codes
The evidence that the Somerton Man was a spy has always been tentative, to say the least.
"I don't think there's compelling evidence — just these scattered circumstantial things that can be explained in different ways," Professor Abbott said.
The discovery of a strange sequence of letters etched on a book of Persian poems linked to the case, and the fact labels had been removed from the man's clothes, have fuelled the theory.
"A lot of people were hanging their hats on the fact that it was a good line to look at, simply because of what was termed a 'code'," author and retired detective senior sergeant Gerry Feltus said.
"From there, the spy theory started to develop because no-one could work out … these lines of letters."
"The climate in that time – 1948 was at the end of the Second World War, and Russia was coming to the fore."
In his book, The Unknown Man, Mr Feltus quotes an old article reporting that a man "told police it was obvious to him the man on Somerton Beach was the famed Russian soldier Marshal Kliment Voroshilov".
"The implication was Voroshilov had been murdered by enemies and dumped."
There was just one problem: Voroshilov, who had himself been complicit in Soviet dictator Joseph Stalin's Red Terror of the late 1930s, was alive in Moscow.
"There's no answer to it.
"You can sit there and argue both ways and walk away and scratch your head."
A link to the Emerald Isle?
Professor Abbott believes the notion of the Somerton Man being a red spy is a red herring.
He is more interested in what can be established for certain.
But there remains one red — or reddish — detail about the Somerton Man: his hair.
"He didn't exactly have ginger hair. [Authorities] said he had mousy hair with flecks of red," Professor Abbott said.
Ireland is not the only country relatively abundant in those with ginger locks, but there is a potentially much stronger Hibernian link to the case.
While most of the Somerton Man's clothing tags were missing, a name was found on several belongings.
"It was spelled K-E-A-N-E on all the items except for one — one had the 'E' missed off the end," Professor Abbott said.
"But there was a little note in the inquest saying that, possibly, that E had faded as that item had been laundered."
Keane is an Irish surname and remains common throughout countries settled by Irish people, such as Australia.
If the Somerton Man was a Keane, Professor Abbott believed he could have been an Australian of Irish descent who had travelled to Adelaide from interstate.
"It's possible he is a Keane or connected to a Keane family in some way — or it could just be a random find: he's picked up some clothes in a second-hand shop."
Hair unlocking clues
Nevertheless, that ginger hair could still prove useful.
Several years ago, Professor Abbott sourced strands of hair from a plaster bust of the man and conducted DNA testing.
"We got something like 16,000 markers, which is quite a big breakthrough, so we proved there is DNA there to be had," he said.
"The other thing we found is what's called his maternal haplogroup — that means the genetic group his mother is descended from."
That haplogroup, H4a1a1a, is "pretty much evenly spread around Europe", so it neither comprehensively confirms nor refutes conjectures of Russian or Irish origins.
But Professor Abbott is not deterred.
"Our efforts are ongoing and we're persisting," he said.
"Every time we have a go at it, we get a bit more."
