The Looking Glass War by John Le Carre

Whether it's James Bond, Jack Bauer or Danger Mouse, most fictional secret agents have one thing in common - they're good at their job.  You don't often get an inept spy, unless it's played for laughs.  There aren't many laughs in this book.

This isn't set in the Circus, home of George Smiley (though he does have a shadowy supporting role), but in "The Department" which deals with military intelligence.  A force to be reckoned with in the Second World War, certainly, but in terminal decline for the two decades since.  The novel starts with a juicy lead about possible missile deployments in East Germany, which gives the out-of-touch spymasters a chance to get the upper hand on the Circus once more.

The story's in three parts - a courier picking up a roll of film in Helskini; a member of the Department sent to Finland to find out what happened; and the re-training of a dusted-off spy who'll be sent behind the Iron Curtain to investigate.  Blunders abound and hilarity doesn't ensue.

There's a lot of good spycraft in this - cover stories, radio communications, the relationship between agent and handler - but more importantly it shows you what happens when good practise isn't followed.  Le Carre was a spy himself for MI5 and MI6, and there's a sense of anger here at good and perhaps misguided people being put at risk because of sloppiness and red tape from those higher up the food chain.

Still plenty of unanswered questions at the end, but for once that was completely justified in the story.  The only problem was a few impassioned and unrealistic outbursts towards the end, but that's pretty minor.  Having said that, this isn't nearly as good as Tinker Tailor, but that's because few books are.