In the depths of Loch Ness, a man's body is discovered, reigniting beliefs in the legendary monster lurking beneath the waves. The deceased is a scientist employed by a secretive Highland laboratory known for producing the highly sought-after Gigi Christner cosmetics.

Detective Jack Drummond faces two intriguing possibilities: Was the scientist's death connected to his obsession with the Loch Ness monster? Or was he silenced to protect the lab's top secret experiment, aimed at discovering a life-prolonging ingredient for their exclusive skincare line?

Journalist Ellie Bruce senses a sensational scoop and relentlessly pursues the story. However, Drummond suspects her true motives might be to undermine his investigation. As Ellie's meddling leads her to a second murder scene, she finds herself arrested.

Has Drummond finally apprehended the killer? Or is there still an elusive culprit on the loose, plotting another deadly act?