The sky is blue, the grass is green, may we have our Halloween? Well, not really. From Merlin and Demons through to the hung-up vampires of True Blood and Being Human, there has been as much supernatural activity on our television screens over the past year as there ever has been. Step back and consider all the recent horror shows, though, and something rather sad becomes apparent. None of them actually wants to scare us any more. That’s been a great loss for TV.

The very premise of True Blood and, in a different way, the BBC’s splendid Being Human, is that their paranormal characters are much like the rest of us. Both series offer pathos and comedy, hot trash, action and thrills, and possibly even moments that shock. What has been lost, however, is the touch of the uncanny, that kind of nameless, ungraspable fear that seeps around you and finally gets inside you.

In both True Blood and Being Human, the undead often explain the particular codes of their existence. But the purest horror defies explanation. In British TV the greatest slice of this kind of inexplicable unease remains Oh Whistle And I’ll Come To You, Jonathan Miller’s brilliant 1968 adaptation of MR James’s ghost story. Spare, bare, black and white, slow, quiet, and starring a crumbling, mumbling, prissy, middle-aged man (Michael Hordern, at his sublime best), who spends most of his time eating or walking a lonely grey beach, it would baffle devotees of Hollywood’s current torture-porn horror if they were told it is supposed to be scary.

But the best way to see Oh Whistle for the first time is to encounter it unexpectedly. No one gets a hook through their face, but I’d like to believe that, were they to find it flickering on their TV late one night when they were alone, even fans of the Saw movies might be drawn in, might feel the atmosphere begin to creep around them.

Ghosts In The Machine , a fun, tidy, seasonal look at the history of ghost stories on TV, gives a lot of time to Oh Whistle, as is only right. Miller is present to explain how one of its most haunting moments was, literally, the oldest ghostie cliché of all: just a bedsheet. Even as he describes how they achieved the effect -- a wire, the sheet, the wind -- as the clip plays again, something about it still works on me in ways I can’t describe. Another contributor, Derren Brown, searching for words, sums it up perfectly as “that oh-what-was-that feeling.”

Gamely narrated by Robert Hardy, the documentary doesn’t judge or delve too far, but simply assembles some of our most notable TV ghosts. And so the deeper phantoms set free by Nigel Kneale’s peerless Quatermass And The Pit and The Stone Tape appear alongside the jokey spooks of Rent-A-Ghost and Randall And Hopkirk (Deceased). As the programmes flit by, though, you can see that oh-what-was-that feeling beginning to drain away. The last breath can be felt in the frantic clips of the BBC’s notorious Ghostwatch, the never-repeated drama of Halloween 1992 that played like a premonitory mix of The Blair Witch Project and Children In Need. Famously, it became the closest the Corporation has had to a War Of The Worlds, when viewers tuning in late mistook it for a genuine live broadcast, and grew convinced Sarah Greene really had been eaten by Satanic cats.

If there is a narrative arc, it’s that this kind of thing -- programmes brave enough to sit you down and say, “Now, I’m going to tell you a scary story…” -- have been replaced by dim reality spookshows such as Most Haunted, in which people trudge darkened houses in grainy green night-vision, jumping at random sounds. The scariest moment in the documentary is the look of grim madness in Yvette Fielding’s eyes as she insists her programme, “isn’t a TV show for entertainment purposes. It’s a GENUINE INVESTIGATION.”

Another interviewee, Mark Gatiss, giggling, proclaims himself a fan of Most Haunted and its ilk, though probably not for reasons Fielding would approve of. With his cursed-house anthology of last Christmas, Crooked House, Gatiss himself has staked an encouraging claim for the creeping terror of the old school. It’s a noble effort, a good place to start, but, enjoyable as it was, Crooked House didn’t have the cosy, yet almost experimental strangeness of Oh Whistle And I’ll Come To You.

There’s no drama in sight that has the courage to keep things so very stark, bare and simple, or the knack to somehow set every second swarming with suggestion.

On Halloween itself, however, there is another documentary that shares qualities with Miller’s ghost story. Wonderland: The Ghostman Of Skye (BBC Two, Saturday, 9.45pm) is a memorable, genuinely haunting film, focusing on one Donald Angus Maclean, above, a man in his eighties, living on the isle with his faithful dog and the memories of his deceased wife, Nina.

Once a missionary, he has a new mission to collect the ghost stories he has heard over the years on Skye: tales of phantom cars, headless women, lights in the night, black shapes on the road, drowned children. To be honest, these stories themselves are not much cop. But somehow, from the figure of Maclean, the brooding landscapes and faces that surround him, and his memories of Nina (he speaks so plainly of their love, a recollection of his hand on her side, that his deep and honest emotion is like something new on television), director Alison McAlpine weaves an extraordinary spell.

Her film taps into how the smallest places hold the greatest isolation. “The curtain that separates us from the beyond is so very thin,” Mr Maclean says, and, in this greatly mysterious grey-green place, you believe it.

Amid the current financial woe, a constant TV lament is that drama must suffer because budgets must be slashed. But if someone with imagination and a good enough story headed out with a skeleton crew and filmed the way that McAlpine films this silent, haunted Skye -- the wind in the trees, the mist on the water, the ominous patience of the blue mountains -- they could produce something to rank alongside the ghost stories of the past. The Ghostman Of Skye is finally less about collecting ghost stories than a new ghost story itself. It runs on a deep current of sadness, as all the best do. It’s small, flawed, a long way from perfect and in hailing distance of greatness.