24 miles long and a mile wide, Loch Ness is one of the deepest, darkest and most mysterious bodies of water in the world. Since the 6th Century, stories have persisted of a monster living in its stygian depths. Are they just stories - or is there genuine hard evidence that 'Nessie' really exists? Join two teams of leading international scientists as they try to unravel the mysterious underwater ecosystem of Loch Ness with the latest technology. The expeditions are frankly sceptical about the existence of the fabled monster - until they too detect inexplicable sonar readings. Listen to first hand eyewitness accounts and discover the remarkable findings of photographic experts as they subject famous pictures of 'Nessie' to intense scrutiny!