Sugar Horse is revealed to be a network of sleeper agents in Russia. They are there for use only in the direst of circumstances. Just as the West's relations are on the brink - there is much sabre-rattling when the US announces its plans to install its missile shield in former Eastern European countries - two Sugar Horse agents are apparently murdered. All of the evidence points to Harry Pearce who is arrested and is forced to undergo severe questioning. Lucas North travels to Moscow to see what he can learn. A member of the MI-5 team is revealed as a Russian mole and is now desperate to be extracted after killing another member of the team.
Stars: Peter Firth, Richard Armitage, Robert Glenister
Director(s): Sam Miller
Writer(s): James Moran, Christian Spurrier