The Flannan Isles are an appropriately dramatic setting for a mystery. A collection of wind-lashed rocks some 20 miles from land in the icy waters of the North Atlantic they have rarely offered much to humans except for shipwrecked mariners or religious pilgrims who are thought to have periodically visited them up until the 8th century (a small shelter stands on Eilean Tighe, and Eilean Mòr hosts a ruined chapel).
In the late 19th century a lighthouse was built on the largest of the islands - Eilean Mòr. Such were the conditions that construction took almost 4 years. When the lighthouse keepers arrived, they became the first permanent residents of the island - and would remain the only inhabitants until 1971, when the automation of the lighthouse was completed and the men sent back ashore for good.
But the island's infamy lives not in its remoteness, but in the fate of three of the first lighthouse keepers who vanished without a trace in 1900. To this day, what became of the men remains unknown - although the mystery is perhaps not so intractable as common belief has it.
In fact, the flavour that the men's disappearance has gathered over the years is owed largely to the last, ominous-sounding entries in the official log. As commonly recounted in books, magazines and websites, the final three days of the men's lives were recorded in staccato, mysterious entries that hint at some Lovecraftian horror:
Dec. 12: Gale, north by north-west. Sea lashed to fury. Stormbound 9pm. Never seen such a storm. Everything shipshape. Ducat irritable. 12pm. Storm still raging. Wind steady. Stormbound. Cannot go out. Ship passed sounding foghorn. Could see lights of cabins. Ducat quiet. McArthur crying.Dec. 13: Storm continued through night. Wind shifted west by north. Ducat quiet. McArthur praying. 12 noon. Grey daylight. Me, Ducat, and McArthur prayed.Dec. 15: 1pm. Storm ended. Sea calm. God is over all.
It was December 15th that the lighthouse was reported as not functioning by the steamer Archtor, who reported it at Oban. It wasn't until the 26th that the relief crew arrived on the island to find the previous incumbents vanished and when the official reports were made. Since then, the fate of the men has been the subject of much theorising - mostly informed by those chillingly enigmatic final log entries.
In fact, Mike Dash has researched the origins of these log entries and can find no earlier record of them than the suggestion that they date to an edition of True Strange Stories published in 1929. Contemporary reports are much more phlegmatic and reports of mysterious log entries are conspicuous by their absence.