When Thomas Longois Lefoy is sent to Tangiers to investigate a German plot involving Moroccan phosphates, he uncovers a sinister Soviet Union involvement in the Asturias miners' strike of 1934 and its unforeseen consequences for Andoni Arriola, a Basque metallurgist. As he delves deeper into the case, he finds himself caught in a web of intrigue involving the Spanish Civil War, the injury and death of British intelligence agents, and the protection of Britain's interests in the iron and copper mining industries. As he travels from Tangiers to Gibraltar, Huelva, and Bilbao, he witnesses the devastating effects of civil war and the destruction of open-cast mining. Along the way, he encounters Heinrich Rathenau, a German industrial chemist seeking refuge, and becomes embroiled in a dangerous game of espionage and political maneuvering that reveals the high stakes of international trade and the human cost of war.