The Island of the title is situated somewhere North of Scotland. Probably based on an island in the Faroes, its isolation is a relevant factor in the plot. The story starts with a Buchan coincidence: he meets a man he has not seen for 20 years, Lombard. Hannay later relates the circumstances of an incident in South Africa when they had saved a man’s life (Haraldsen) from business rivals. They swore to protect his heirs in the future. They are then called on by Haraldsen’s son to protect him from the son of the original villain, Troth. Troth’s son has been joined by various others, who are determined to seize the fortune held by Haraldsen. Sandy Arbuthnot (Green Mantle, Three Hostages) joins Hannay and Lombard to foil a kidnap plot and get Haraldsen’s family to safety. Arbuthnot reveals that a far bigger desperado D’Ingraville, whose path he has crossed previously in South America, (The Courts of the Morning) has taken control of the gang. The final action takes place on the Island of Sheep where anything is possible due to the absence of the rule of law.