"It stood alone in the Celtic Sea: the oil-rig TARACO 5, a Trojan Horse aimed at the very heart of Britain. Acquired by blackmail and extortion, staffed by the KGB, it represented the ultimate threat to the security and the very existence of the country whose economic future it symbolized. ... The Moscow Horse."
Department RE is interested in TARACO 5, so much in fact it will send its two best agents to work separately in resolving the matter: Cristal Vengan and Ewan Scott.