Ten years ago, an Irish pub owner was clearing land for a driveway when his digging exposed an unusually large flat stone. The stone, in turn, obscured a dark gap underneath. He grabbed a flashlight to peer in.
"I shot the torch in and saw the gentleman, well, his [bones]," Bertie Currie, the pub owner, said this week.
The remains of three humans, in fact, were found behind McCuaig's Pub in County Antrim, Northern Ireland. And though police were called, it was not, as it turned out, a crime scene.
Instead, what Currie had stumbled upon was an ancient burial that, after a recent DNA analysis, challenges the centuries-old account of Irish origins.
From as far back as the 16th century, historians taught that the Irish are the descendants of the Celts, the Iron Age people who originated in the middle of Europe and invaded Ireland somewhere between 1000BC and 500BC.
Yet the bones discovered behind McCuaig's tell a different story of Irish origins, and it does not include the Celts.
"The DNA evidence based on those bones completely upends the traditional view," said Barry Cunliffe, an emeritus professor of archaeology at Oxford who has written books on the origins of the people of Ireland.
DNA research indicates that the three skeletons found behind McCuaig's are ancestors of the modern Irish and they predate the Celts and their purported arrival by a thousand years or more. The genetic roots of today's Irish, in other words, existed in Ireland before the Celts arrived.
"The most striking feature" of the bones, according to the research published in the Proceedings of the National Academy of Science journal, is how much their DNA resembles that of contemporary Irish, Welsh and Scots. (By contrast, older bones found in Ireland were more like Mediterranean people, not the modern Irish.)
Radiocarbon dating shows that the bones discovered at McCuaig's go back to about 2000BC. That makes them hundreds of years older than the oldest artefacts generally considered to be Celtic - relics unearthed from Celt homelands of continental Europe, most notably around Switzerland, Austria and Germany.
Where this leaves the pervasive idea that the Irish and other people of the area are "Celtic" is unclear. It depends on the definition of Celtic.
There are essentially two definitions - and two arguments.
The first revolves around language. The Irish language is, like Welsh and Scottish Gaelic, part of a group that linguists have labelled Celtic. The languages seem to have emerged after a similar evolution from Indo-European.
What is unclear is whether or not the term "Celtic" is an appropriate name for that group of languages.
To be sure, some think that Celtic languages originated with the Celts on continental Europe and later spread to Ireland, Wales and Scotland. This is the traditional view, and it dovetails with the idea that the Celts moved into Ireland during the Iron Age.
But over the past decade, a growing number of scholars have argued that the first Celtic languages were spoken not by the Celts in the middle of Europe but by ancient people on Europe's western extremities, possibly in Portugal, Spain, Ireland or on the western edges of the British Isles.
The second line of argument arises from archaeology and related sources.
Numerous digs, most notably in Austria and Switzerland, have traced the outlines of the Celts. The artefacts offer evidence going back as far as about 800BC. The Celts sacked Rome around 390BC and attacked Delphi in Greece in 279BC.
It seemed plausible that this group that had invaded Rome had invaded Ireland as well, and in the standard view, it was this people that eventually made it to Ireland.
In recent years, some archaeologists have proposed that the traditional story of the Celts' invasion was, in a sense, exactly wrong - the culture was not imported but exported - originating on the western edge of Europe much earlier than previously thought and spreading into the continent.