George Smiley has become acting Chief of the Circus, or rather what remains of it. For the credibility of the British Secret Service has been shattered by his unmasking of a traitor within. It is being starved of funds by Whitehall, and sidelined by its American cousins. Smiley's appointment, therefore, seems more like retribution than promotion.
Yet from the first he goes onto the attack. His adversary is Karla, workname of the Soviet case officer who masterminded the Circus's ruin. His battleground is Hong Kong, and his choice of weapons is the Honourable Gerald Westerby, Eastern hand and Fleet Street hack.
Westerby's odyssey takes him to collapsing Cambodia and Vietnam, to the insurgency area of North East Thailand and finally to the southernmost tip of the Hong Kong archipelago, to the very edge of the China Sea. His belated coming of age, his bounding humanity striving to get out, his courage and his recognition of love, are set in mounting dramatic contrast to the ever-growing needs of the service that claims his allegiance.