The biggest search for the Loch Ness Monster in five decades takes place in the Scottish Highlands on Saturday, as researchers and enthusiasts from around the world meet to try to track down the elusive Nessie.

The expedition will deploy drones with thermal scanners, boats with infrared cameras and an underwater hydrophone to try to unravel a mystery that has captivated the world for generations.

"It's always been our goal to record, study and analyze all manner of natural behavior and phenomena that may be more challenging to explain," said Alan McKenna, of co-organizers Loch Ness Exploration.