Sherlock Holmes and the mystery of the reappearing Loch Ness Monster...

A model Nessie used for the 1969 movie The Private Life of Sherlock Holmes looks to have been identified deep below the surface of the water by a team of scientists surveying the loch using sonar imaging equipment.

"We have found a monster, but not the one many people might have expected," said Loch Ness expert Adrian Shine, who is working with VisitScotland on a project to map the ecology of the loch and determine the possibility of a real-life Nessie.

"The model was built with a neck and two humps and taken alongside a pier for filming of portions of the film in 1969," he told BBC News Scotland.

"The director did not want the humps and asked that they be removed, despite warnings I suspect from the rest of the production that this would affect its buoyancy.

"And the inevitable happened. The model sank."

The Private Life of Sherlock Holmes stars Sir Robert Stephens as Holmes, Colin Blakely as Dr Watson and Christopher Lee as the detective's brother, Mycroft.

The film centres on the "real" Sherlock Holmes, who is rather different from the persona created by his friend Watson. It features a scene in which Watson apparently encounters the Loch Ness Monster, which turns out to be a submarine disguised as Nessie that was built by Mycroft for the British Navy.

So to clarify: a real-life prop built as a fake Loch Ness Monster for a film about the real Sherlock Holmes behind the fake persona has been discovered at the bottom of the real Loch Ness.

Elementary, right?