After the ceasefire in Laos in February 1973, London forbids Colonel Jason Rance, the British Defence Attaché in Laos, from continuing his search for four Lao 'moles', who work within the Communist Party and wear a dedicated ring as a talisman. Unsanctioned contingency plans are therefore made by others for Rance to continue his work with the moles, the 'Four Rings', in an unattributable Operation Four Rings. But Rance remains ignorant of the plan and does not know he is in imminent danger. The communists now suspect the Four Rings as well as Colonel Rance and they launch their own Operation Four Rings: to kill the four moles and the British Defence Attaché. The tightest of races ensues. Based on historical fact and the author's personal experience, Operation Four Rings is the fifth in a series of books involving Gurkha military units and includes Operation Black Rose, Operation Janus, Operation Blind Spot and Operation Stealth. The author, a retired Gurkha colonel, draws on real characters and events he witnessed across various theatres of war.