A MOURNFUL howl echoed through the mist as we explored the ruined remains of the 800-year-old Holy Trinity Church in Buckfastleigh, on Dartmoor, providing a worrying reminder of the legend associated with this lonely place.
Fortunately - or maybe unfortunately - the howl wasn't coming from a spectral hound, but from me ... as I tried to create the proper atmosphere for the story I was investigating.
This was once the parish church of Squire Richard Cabell, whose wicked life and - more importantly - unquiet death inspired Sir Arthur Conan Doyle to write the classic Sherlock Holmes story The Hound of the Baskervilles.
The local people believed that after he died, about 1656, the evil squire continued to ride and hunt across the moors with a pack of spectral hounds. To confine his unquiet spirit to the grave, they built a concrete prison over the top of his tomb.
It is said that even today, anyone foolish enough to poke fingers through the bars of his tomb runs the risk of having them bitten, and those visiting at night have sometimes reported seeing a red glow from the tomb.
It was a cold, dank Dartmoor day when we came calling at the church, just such a day as you might expect a pack of spectral hounds to emerge with slavering mouths from the clouds hovering over the surrounding farmland, so I didn't take any liberties.
I walked carefully round the rows of gravestones black with moss and age, looking for Squire Cabell's. In the end it was easy to pick. The grave itself is fairly nondescript, with only its position close to the church door underlining the important social position of its tenant.
What makes it stand out from the hundreds of others is the solid concrete shelter, complete with slate roof and thick iron bars, erected around it. Peering through the bars, I could see the grave itself or, to be more accurate, I could see the big white slab the locals put on top of the grave as a further safeguard against him escaping.
It was hard to imagine Squire Cabell getting out of that prison but I still kept my fingers away from the bars and maintained a wary lookout for strange shadows.
After all, the story of the ghastly squire is only part of the legend of this lonely church. According to the website, Legendary Dartmoor, the devil tried to stop a church being built on this site and was foiled only when a steep staircase with 196 steps was built to provide access (maybe Satan is out of condition).
In the 19th century, Holy Trinity's isolated location made it a favourite site for bodysnatchers. Around the same time, the spire was hit by lightning and broken off. A few years later arsonists broke in and set the church on fire. During World War II, the stained-glass windows were smashed by bombs.
And in 1992, arsonists broke in again - devil worshippers were blamed - and started another blaze which gutted the building.
Services are still held in the shell of the church from time to time, and the peal of bells in the tower was recently restored, but despite these efforts to keep the Christian spirit alive the place does have a rather macabre air.
That's also true of Dartmoor in general. It's incredibly beautiful, filled with quaint old cottages, cute ponies and horned sheep, rushing rivers, wide grassy moors and spectacular rocky outcrops. But when the mists roll across the landscape and the light fades, it's a rather malevolent place.
Of course, some of Dartmoor's scary reputation arises from the centuries-old presence of Dartmoor Prison, a sprawling stone complex around which has grown the settlement of Princeton, now the largest town on the moor.
Princeton's other notable building is the old Duchy Hotel, once the haunt of celebrities from Winston Churchill and Lord Tennyson to Prince Albert and Conan Doyle, who in 1901 wrote several chapters of The Hound of the Baskervilles there. These days it is the High Moorland Visitor Centre, with information about the moors and exhibitions on the history and wildlife of the region.
Dartmoor is still a working prison, though, contrary to its fearsome reputation, it holds mostly non-violent and white-collar criminals. A stone building down the road has been converted into a prison museum and a shop selling craftwork made by the prisoners. My favourite was a pottery doorstop depicting a couple of burglars with bags of swag and a sign proclaiming, "Neighbourhood Watch".
But I was drawn to the prison. I sat over the road from its massive gates for a while, hoping the light would improve so I could get a nice photo, but my presence seemed to upset a man who was waiting right beside the gates.
When he saw my camera, he quickly scuttled off to hide behind one of the stone pillars, peering out from time to time to check if I was still there.
I wonder what his story was? I'm sure Sherlock Holmes would have been able to work it out.
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