Sir Humphrey Appleby criticises Bernard over an answer given by Jim Hacker during Prime Minister's Questions. It seems that the PM denied authorising the bugging of an MP's telephone, and the question was not referred beforehand to Sir Humphrey, who is in charge of security matters.

The pair go to see the Prime Minister in the Cabinet Room, where he is cock-a-hoop over his recent performance in the House of Commons. He insists that the two civil servants hear a verbatim report of PMQs and Sir Humphrey finds it difficult to interrupt. However, he eventually brings Hacker down to earth with typical verbiage, which he translates. The PM has lied to Parliament — the ultimate political sin. The MP, whose name is Hugh Halifax, was indeed the subject of government surveillance up until a few minutes ago, and Hacker wishes to know why he wasn't informed. Sir Humphrey tells him that there are some things that he doesn't need to know. When Hacker protests that he has a right to be aware of everything, the Cabinet Secretary explains that nobody willingly conceals anything from him; however, decisions are occasionally taken not to reveal information, which apparently makes all the difference.

Sir Humphrey receives an invitation to appear before a House of Commons Privileges Committee to answer the allegations concerning Hugh Halifax. He confesses to Bernard that even he is at a loss to know how to proceed. Then, over a sherry, he tells Bernard that he is to participate in a documentary on BBC Radio 3 about the structure of government. Sir Humphrey is concerned that if he turned down the opportunity, then his retired predecessor Sir Arnold Robinson would be interviewed and would outshine him. Bernard is mildly shocked that someone who is supposed to be "faceless" is making a media appearance, but as Sir Humphrey reminds him, "They don't show your face on radio." Although permission from the PM is required, Bernard doesn't feel that this will pose a problem, as hardly anyone listens to Radio 3.

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Wikipedia