It is 1958. Chief Superintendent Frederick Troy of Scotland Yard, newly promoted after good service during Nikita Khrushchev's visit to Britain, is not looking forward to a Continental trip with his older brother, Rod. Rod was too vain to celebrate being fifty so instead takes his entire family on 'the Grand Tour' for his fifty-first birthday: Paris, Siena, Florence, Vienna, Amsterdam. Restaurants, galleries and concert halls. But Frederick Troy never gets to Amsterdam.

After a concert in Vienna he is approached by an old friend whom he has not seen for years - Guy Burgess, a spy for the Soviets, who says something extraordinary: 'I want to come home.' Troy dumps the problem on MI5 who send an agent to debrief Burgess - but when the man is gunned down only yards from the embassy, the whole plan unravels with alarming speed and Troy finds himself a suspect.

As he fights to prove his innocence, Troy discovers that Burgess is not the only ghost who has returned to haunt him...