For fifty years, Iris has accepted the curse that blighted her life. By night, she is a lonely immortal in human form, destined to walk the shores of the place that was once her home. By day, she is Moireach, a terrifying sea creature imprisoned in the murky depths of Loch Moine.

But when bodies begin appearing on the misty banks of the loch, Iris suddenly finds herself in mortal danger. The residents of Kilmara fear that the monster, which for centuries has been rumoured to haunt the deeps of the loch, has awoken again. And so a hunter - the rugged, ruthless Henry Carver - is summoned to find the monster, and to slay it.

Iris has to find a way to break her curse before she is killed for crimes she cannot, will not, believe she has committed. But Moireach's dark influence over her grows more powerful day by day, whilst Iris finds herself falling for the very man sent to annihilate her in an impossible attraction. And as bodies keep appearing on the loch, and she and Henry are drawn closer together in a dangerous game, Iris is forced to question who she really is and what - or who - she is willing to sacrifice to break the curse.