Lights Out: The Flannan Isles Lighthouse Mystery
August 01, 2025At the turn of the twentieth century, an enduring mystery began to unfold on the Flannan Isles – a remote island group in the Outer Hebrides of Scotland. Strange circumstance and generations of folklore have concocted an intricate web of accounts, but none fully explain what caused three men to vanish without a trace.
An overturned chair, a half-eaten meal, stopped clocks and a fire that hadn’t been lit for days punctuated the perplexing scene that confronted relief lighthouse keeper Joseph Moore as he entered the kitchen of the Eilean Mòr lighthouse on Boxing Day 1900. As he searched throughout, more puzzling details emerged. Why was one set of oilskins still hanging up in the hallway given the recent stormy conditions? Why was the last entry in the logbook from the 13th December? And why was there absolutely no sign of the three dependable lighthouse keepers, James Ducat, Thomas Marshall and Donald McArthur?
Cause for concern
Moore had been aboard the Hesperus, a lighthouse tender vessel on a routine visit to the island. As the boat got close, they raised a flag to signal their arrival – but got no response. They sounded the horn and sent a flare up – and still, no sign of life. A feeling of disquiet washed over the men as Moore clambered out to investigate.
Unknown to him at the time, another vessel – the SS Archtor – on the final leg of a voyage from Philadelphia to Leith in Edinburgh had passed the ‘Flannans’ at around midnight on the 15th December and saw no light from the lighthouse. The captain was convinced something was wrong and intended to report it as soon as they made it into port, but the ship ran aground in the Firth of Forth and the message didn’t get to the Northern Lighthouse Board until after Christmas.
Another ominous sign came from 18 miles east, on the Isle of Lewis. With no radio communication between the Flannan Isles and Lewis – where the relief vessel was anchored – a gamekeeper named Roderick MacKenzie was paid by the lighthouse board to keep a lookout for signals from the lighthouse and report any failures.
Standing on Gallan Head, he had now not seen any beams of light for eight consecutive nights. The island had been obscured by ‘haar’ – a form of sea mist – for much of that time. For the first seven nights he told himself that the weather was simply obstructing the light. On the eighth night as the weather started to clear, he filled with dread that something was wrong, cursing his inaction. Bafflingly, there’s no record of MacKenzie officially reporting the incident.
A quick exit
One thing we know for sure is that when Joseph Moore entered the room, a scene of disarray held vital clues to the fate of the three men who had apparently left in a hurry. He had rowed ashore himself through now calmer water and began making his way up steep stone steps, consumed with foreboding, according to his personal account at the time. Unusually, the entrance gate was closed. After passing through more closed doors, he reached an open one into the kitchen. As he quickly surveyed the scene, an eerie frisson filled the air. He quickly checked their bunks – all empty and just as they would have left them in the morning – before making a hasty retreat, now certain that something serious had unfolded here.
The alarm was raised and Moore was ordered back to the island along with other crew members to maintain the light and search for any sign of the men on Eilean Mòr. While everything appeared to have been left in proper working order in the lighthouse, their painstaking inspection of every nook and cranny on the island uncovered evidence of ferocious sea conditions.
On the west side, an old box halfway up the rail line for landing and mooring ropes and tackle had been washed away, with ropes strewn across the rocks. Iron railings along the passage connecting the railway to the footpath had been wrenched from their foundations and broken in several places. Further railings around the crane had also been taken by the tide and a rock weighing at least a tonne had been moved a considerable distance downhill.
Fact and fiction
Now their attention turned to unsettling details found in the logbook – the whereabouts of which is today unknown. The veracity of these entries has been hotly disputed over the years, with a consensus building that some were most likely fabricated as the story of the Flannan Isles vanishing became more embellished with every retelling.
“December 12th: “Gale north by northwest. Sea lashed to fury. Never seen such a storm. Waves very high. Tearing at lighthouse. Everything shipshape. James Ducat irritable.” “Storm still raging, wind steady. Stormbound. Cannot go out. Ship passing sounding foghorn. Could see lights of cabins. Ducat quiet. Donald McArthur crying.”
“December 13th: “Storm continued through night. Wind shifted west by north. Ducat quiet. McArthur praying”. “Noon, grey daylight. Me, Ducat and McArthur prayed.”
“December 14th: No logbook entry. Time noted for ‘extinguishing’ the light visible on slate [for transferring to the logbook].
“December 15th: No logbook entry. Barometer and thermometer readings recorded, along with a description of the wind conditions at 9am. “1pm. Storm ended, sea calm. God is over all.” [Written on slate by James Ducat for transferring to the logbook]
Eleven days later, the first contemporary account summed up the facts as they were known and interpreted at the time:
“A dreadful accident has happened at Flannans. The three Keepers, Ducat, Marshall and the occasional have disappeared from the island. On our arrival there this afternoon no sign of life was to be seen on the Island. Fired a rocket but, as no response was made, managed to land Moore, who went up to the Station but found no Keepers there. The clocks were stopped and other signs indicated that the accident must have happened about a week ago. Poor fellows they must have been blown over the cliffs or drowned trying to secure a crane or something like that. Night coming on, we could not wait to make something as to their fate. I have left Moore, MacDonald, Buoymaster and two Seamen on the island to keep the light burning until you make other arrangements. Will not return to Oban until I hear from you. I have repeated this wire to Muirhead in case you are not at home. I will remain at the telegraph office tonight until it closes, if you wish to wire me.” – Telegram from the Master of the Hesperus, 26th December 1900.
Rogue wave
So, what explains all of the anomalies that make this such a bewildering case to solve? The most plausible explanation is the rogue wave theory. It posits that Marshall and Ducat had gone out to secure mooring and landing ropes contained in a crate around 110 feet above sea level – most likely dislodged during the recent storm. A freak wave then rushed up the cliff, taking the two men to their deaths.
MacArthur would have waited in the lighthouse in line with protocol before heading out to see what was taking them so long. He would have no sense of panic at this point, which would explain why doors were shut – but what about that upturned chair? Had he perhaps witnessed the colossal roller approaching and run out to try and save his colleagues, only to be also swept away while searching for them, with the wind randomly blowing doors shut?
But could a wave of such height really have occurred from seas that were at that point believed to be relatively calm? Well, rogue waves of that magnitude have been recorded before, such as the one that caused considerable damage to the Fastnet Lighthouse off the south-west coast of Ireland in 1985, which was estimated to be a staggering 157 feet at its peak. The first scientifically verified rogue wave is thought to have been recorded at the Draupner oil platform in the North Sea in 1996, measuring 85 feet. And on 4th February 2013, buoys off the west coast of the Isle of Lewis detected average wave heights of 45 feet during hurricane-force winds.
Making sense of the mysterious
The official report into their disappearance dispensed with the far-fetched and frankly ridiculous theories that were swirling around in public discourse, and leaned towards a likelihood that the men drowned. It refers to a final draft log entry made on the 15th December, but frustratingly doesn’t say what was said. Given the growing speculation over the years that the final entries may have been altered or invented, the logbook remains a crucial missing piece of the puzzle.
The report confirmed that a wooden crate containing ropes and crane handles – stored within a crevice some 110 feet above the sea – had disappeared, with some of its contents left by nearby rocks and entangled around the legs of the crane. All were still coiled up. A life buoy had been torn from railings at the same height. Inquiries were made into the record kept by the gamekeeper Roderick MacKenzie on Lewis, which found that a signal from the lighthouse had only been observed twice from the 7th December to Christmas Day.
An obvious explanation?
125 years on, there’s still much that doesn’t add up about the vanishing of James Ducat, Thomas Marshall and Donald McArthur. As is often the case when there’s a lack of information, the vacuum gets filled with half-truths and falsehoods. Over the years, fact and fiction have become more and more intertwined.
But for this author at least, when you delve into the Flannan Isles Lighthouse mystery, you find that there doesn’t appear to be much mystery at all, given the little evidence we do have to go on. There were clear signs that a rogue wave had impacted the island, and so it is right that this remains the most plausible explanation. The real mystery surely lies in how these rogue waves form in the first place – something that cutting edge science is currently unravelling.