Julia Probyn - journalist, amateur sleuth and occasional spy - is sailing off the west coast of Scotland with her cousin Colin when they stumble upon a suspicious sky-blue pole, rising from the ground on the desolate island of Erinish Beg. Colin, who works for the British Secret Service, immediately suspects Russian surveillance.

Military Intelligence sends Colonel Jamieson to investigate this find, and together he and Julia must unravel the mystery. But as the Cold War rages, the pair are soon to find out that the antenna-like pole is only the beginning. As the conspiracy grows, so too does their affection for each other, which seems rather likely to complicate matters.

The Dangerous Islands, book four of The Julia Probyn Mysteries, is a tale of love, adventure, and espionage.