Isa McQuiston is caught between two worlds. Strange creatures are attacking her people, their injuries beyond her medical expertise. More than one fisherman has been tossed ashore by the waves, drained of blood, a severed tentacle piercing his flesh. To find answers, she must forge a cautious alliance with the outsider making inquiries...even if he does present an almost irresistible temptation.

Dr. Alec McCullough, an injured naval officer, is restless and bored. Until his brother - an agent for the Crown - offers him an assignment: investigate a recent rash of unexplained octopus attacks. On the wet and windy Hebridean Isles, his every effort is met with resistance. Coaxing an attractive young widow - the local healer - to allow him to examine the latest victim only leads to further complications.

A fusion of living and mechanical components, the creatures follow instinct but also command. Together, they uncover layers of deceit, revealing traitorous tentacles that entangle both their lives. As those behind their creation callously sacrifice innocent lives in pursuit of their goals, Isa and Alec struggle to forge a future together while attempting to prevent a disaster of international proportions.