Generally the system is referred to as the "permanent state". The oral and written tradition of various parts of the civil services has a very large influence on what policy can actually get made. Certain ideas keep popping up in a way that suggests the same briefing paper is simply being presented as a new idea to each new minister.
The secret part of the permanent state is even more persistent, as it keeps all information relating to its operations secret. This can include even quite large chunks of the budget: https://en.wikipedia.org/wiki/Zircon_affair
Pullquote from the end of that page: "We saw the spectacle of police being sent to raid the BBC headquarters in Glasgow in the middle of the night.... We saw the Zircon tapes seized as an elaborate blind." Darling said that the cabinet episode concerned "... the election campaign of 1983, and the fact that the Government sought to undermine and spy on the citizens of this country."