Jim Hacker gets back to his apartment above 10 Downing Street just in time to sit down with his wife, Annie, and watch the end of a television news bulletin. He is upset that the report of his performance at Prime Minister’s Questions, which he regarded as one of his best, has been dropped in favour of a story concerning Benjy, an Old English sheepdog owned by an eight-year-old girl, which has strayed on to an artillery range on Salisbury Plain. The Ministry of Defence has ruled out a rescue, and Annie is aggrieved at its decision.

Back at work, Hacker meets with Sir Geoffrey Hastings, the Director General of MI5, who has a serious disclosure. It has transpired that the late Sir John Halstead, Sir Geoffrey’s predecessor during the 1960s, was a Russian spy. In the 1970s, there was an inquiry into his activities that cleared him, but which overlooked several key points in such a fashion that suggests either incompetence or collusion. However, its official head was a senile peer, and most of the actual inquiry was carried out by none other than Sir Humphrey Appleby. The Prime Minister is urged to conduct an inquiry of his own, in order to ascertain that the Cabinet Secretary is “one of us”.

Hacker meets Sir Humphrey and is at first more concerned with his plummeting opinion poll ratings. He wishes to be more relevant, but Sir Humphrey points out that the only topic occupying the nation at present is the lost dog on Salisbury Plain. The PM then turns to his "security matter". Sir Humphrey readily admits that government security inquiries are primarily designed to kill press speculation, and in any case, he was certain of Sir John Halstead’s integrity. He is therefore unprepared for the truth, and still can’t quite believe it when Hacker enlightens him. He protests that he was a busy man at the time and couldn’t look into everything, as "you never know what you might find". Nevertheless, Hacker tells him, he was either in collusion or incompetent. The PM is minded to send Sir Humphrey on gardening leave until the matter is fully investigated. However, Hacker confesses that he has no experience of such things and wishes to speak to Sir Humphrey’s predecessor, Sir Arnold Robinson, to ask his advice. He forbids Sir Humphrey to contact Sir Arnold beforehand, and the mandarin states that he "wouldn’t dream of it".

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