Whips pride themselves on their secrecy and discretion. Reporter Michael Cockerell uncovers their shadowy world and reveals how they operate. How close to reality is the fictional Chief Whip Francis Urquhart, in the drama series House of Cards?  Government Whips can make or break ministers and ensure they know all the secrets of the private lives of their fellow MPs. One Tory MP claims that the Whips are a gestapo, but another says they are democracy's unsung heroes - as necessary for Parliament as sewers are for civilisation.

Westminster's Secret Service

A compelling account of Juan Pujol, an extraordinary Spanish double agent during WWII who helped change the course of history.