The Loch Ness monster is back — and there's video.

A man has captured what Nessie watchers say is possible footage of the supposed mythical creature beneath Scotland's most mysterious lake.

"I couldn't believe my eyes when I saw this jet-black thing, about 45 feet long, moving fairly fast in the water," said Gordon Holmes, the 55-year-old lab technician from Shipley, Yorkshire, who took the video Saturday.

Click here to watch the new 'footage' of the Loch Ness Monster.

Nessie watcher and marine biologist Adrian Shine viewed the video and hoped to properly analyze it in the coming months.

"I see myself as a skeptical interpreter of what happens in the loch, but I do keep an open mind about these things and there is no doubt this is some of the best footage I have seen," said Shine, of the Loch Ness 2000 center in Drumnadrochit, on the shores of the lake.

He said the video is particularly useful because Holmes panned back to get the background shore into the shot. That means it was less likely to be a fake and provided geographical bearings allowing one to calculate how big the creature was and how fast it was traveling.

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Holmes said whatever it was moved at about 6 mph and kept a fairly straight course.

"My initial thought is it could be a very big eel — they have serpent-like features and they may explain all the sightings in Loch Ness over the years."

Loch Ness is surrounded by myth. It's the largest inland body of water in Britain, and at about 750 feet to the bottom, it's even deeper than the North Sea.

"There are a number of possible explanations to the sightings in the loch. It could be some biological creature, it could just be the waves of the loch or it could some psychological phenomenon in as much as we see what we want to see," Shine said.

While many sightings can be attributed to a drop of the local whisky, legends of Scottish monsters date back to one of the founders of the Christian church in Scotland, St. Columba, who wrote of them in about 565 A.D.

More recently, there have been more than 4,000 purported Nessie sightings since she was first caught on camera by a surgeon on vacation in the 1930s. [That famous photograph was revealed 60 years later to have been a hoax involving a sculpted head mounted on a toy submarine.]

Since then, the faithful have speculated about it is a completely unknown species, a sturgeon — even though they have not been native to Scotland's waters for many years — or even a plesiosaur, a long-necked aquatic reptile that went extinct with the dinosaurs.

Real or imagined, Nessie has long been a Scottish emblem. She has been the muse for cuddly toys and immortalized on T-shirts and posters showing her classic three-humped image.

On Thursday, a group of Scottish business owners launched a bid to nominate Loch Ness for World Heritage site status — though they cited its natural beauty, not Nessie.

The Destination Loch Ness consortium must submit the nomination to the British government, which would decide whether to forward it to UNESCO.

The Scottish media is skeptical of Nessie stories but Holmes' footage is of such good quality that even the normally reticent BBC Scotland aired the video on its main news program Tuesday.