Nessie is emerging again in a new film - and boosting Scotland's economy, says Jonathan Glancey; Our best-loved beastie of the deep emerges a star

PROFILE: the Loch Ness monster

Tonight, as murky Highland mists roll over the inky waters of nearby Loch Ness, a select gathering will attend the premiere of Loch Ness in the old Inverness Scala. The film (brought to you by the makers of Four Weddings and a Funeral and starring Ted Danson, Ian Holm and Joely Richardson) has its London premiere next Friday.

Between now and then, expect Nessie herself (himself?) to take a bow. For the tourist-baiting Loch Ness monster has never been one to let a timely photo-opportunity pass her by.

Sceptics - as prolific as the monster is rare - believe that Nessie is nothing more than a prop in the wardrobe department of local tourist boards. Their case is a strong one - following hard on the kilts of the Hollywood productions Braveheart and Rob Roy, Loch Ness is expected to spur on a vigorous new American tourist invasion of the Scottish Highlands.

Half a million visitors a year come to Loch Ness in the hope of catching a glimpse of Nessie. Of these, 300,000 visit the official Loch Ness monster museum at Drumnadrochit, a village on the edge of the loch. They have made Ronnie Bremner, the museum's owner, a multi-millionaire. Between them they spend pounds 25m a year in the vicinity of the loch, yet the only monsters they see are the cuddly ones bought from Bremner's souvenir stall.

The first 20th-century sighting of the monster was by Mr and Mrs John Mackay, proprietors of the Drumnadrochit Hotel, in 1933. The Inverness Courier snapped up the story (the beastie was dubbed the Loch Ness monster by Dr Evan Barron, that paper's editor), which in turn led to an invasion by hacks from Fleet Street's Daily Beasts and Daily Brutes. By now, it was all but impossible to book a room in the Drumnadrochit Hotel.

On 19 April 1934, Lt Col Robert Wilson, a Harley Street gynaecologist, caught the monster on camera. The "surgeon's photograph" was a worldwide sensation, and, until exposed as a fake 60 years later,remained the most convincing evidence anyone had of Nessie's existence.

Lt Col Wilson had in fact taken part in a hoax organised by Marmaduke Arundel Wetherell, actor and adventurer. The serpentine head and neck rearing up from the loch's deep and peaty waters were nothing more than a toy submarine in heavy disguise. Wetherell's stepson, Christopher, eventually revealed the hoax on his deathbed, aged 90, in November 1993.

For the monster's millions of fans, this was a setback - but little more than that. After all, which Christian has ceased to believe in the Saviour since the Turin Shroud was shown to be a brilliant thirteenth- century fake?

In any case, although the monster is supposed to be a plesiosaur (a marine dinosaur, presumed extinct 70 million years ago), no one is quite sure. Over the past five years, Nessie has been described as an alien sent to observe life on Earth, a ghost capable of transforming itself into solid matter, a giant frog, a loch-locked whale and the mother of all sturgeons.

It does seem odd that when the Hubble Space Telescope can spot galaxies billions of light years from our own, Nessie remains as elusive as ever. As elusive, in fact, as Big Foot (or Sasquatch), the Abominable Snowman (Yeti) and the Beast of Bodmin; as hidden as sibling marine monsters such as Morag, the beast of Loch Morar, the Lambton Worm, the watery Welsh dragon that hides away in Lake Vrnwy, and the slobbering Beast of Bolsover.

There are records of monsters lurking in Scottish lochs dating back to the country's conversion to Christianity. Nessie's firstappearance seems to have been 565AD, when she set upon St Columba and his holy band. After this episode, sightings were few and far between until the 20th century. According to the BBC reporter Nicholas Witchell, author of The Loch Ness Story and one of the monster's most insistent fans, this paucity of sightings reflects the fact that before the arrival of the A82 tourist road skirting the east coast of the lake in 1933, Loch Ness was extremely remote.

And it's not just tourists who are eternally intrigued by Nessie's possibilities. Shortly before Christmas, Tritech International, a firm of North Sea boffins, launched its "Nessie-detecting sonar system" at the Offshore Europe Oil Exhibition in Aberdeen. Earlier last year the veteran underwater explorer Alan Whitfield recorded previously unheard "grunts and groans" of a creature that could only be Nessie. While most serious biomarine expeditions today study Loch Ness because it is inherently fascinating, it is still the case that funding can be better obtained by riding on the back of the monster myth.

Nevertheless, the famously deep (possibly 1,000ft in places) and dark waters of Loch Ness (the most powerful submarine lamps enable the human eye to see 15ft into the gloom) may well hold undiscovered secrets. Even a prehistoric monster.

Our need for monsters seems to be deeply rooted. The British Isles have few, if any, large or fierce animals: the last wolf was shot in the Highlands in 1743. Nessie fills a gap. And with monster myths, we can feed our desire for mystery. It would be a sad day for many of us if Nessie were ever caught in a net instead of on blurry celluloid and out-of-focus videotape. In 1993, the American Sun newspaper ran a spoof story, with photographs, of how Nessie had been caught. As Americans are the monster's most voracious fans, the Sun knew it would have a captive audience that day.

Did the same goal motivate the editor of Popolo d'Italia in 1941? The Fascist daily told of how brave Italian pilots had flown over Loch Ness and blown the monster into a tangle of spaghetti. An Italian bomber over Scotland? That was surely a bigger hoax than the surgeon's photograph of 1934. In Germany, Josef Goebbels had already taken a pot-shot at Nessie in an article he signed for Hamburger Illustrierte in 1940; any nation, thundered the Minister for Propaganda, that believed in such tosh was clearly monstrously stupid and thus incapable of winning the war.

Today, in the international war for tourists' attention, the Stirling and Trossachs region is doing very nicely, according to Alastair McPherson of the Scottish Tourist Board. Rob Roy and Braveheart produced a boom and, he believes, Loch Ness may treble the number of visitors this year to 1.5 million, boosting revenue to a healthy pounds 350m. The tourist industry in Scotland employs 180,000 people.

So here's a toast from the banks, braes and ringing tills of bonny Loch Ness: to Hollywood. And thanks, of course, to Nessie, a solitary, 70- million-year-old monster, for playing her supporting role so well and keeping her monstrous head down until needed.