A Three Pipe Problem

The moment I saw the thick white envelope I knew that it was from the Diogenes Club.  Inside  was a plain sheet of the very best paper on which, in a hand that I knew so well, were the words "Come at Once". The signature too was not unknown to me.  There it was in the strong male hand of a man - and what a man!  "Sherlock"  As ever the word sent an agreeable frisson down the back of my neck.  The man I had admired for so many years was back.  Did I write "admired"?  Nay you might almost say "loved" for so closely had I lived with him under Mrs. Hudson's hospitable roof - perhaps so much as to make my wife forget my first name.  Sometimes she called me "James" and at other times I was "John".  (Such forgetfulness is common among the fair sex)
Fog swirled about me as I knocked on the door of 221b in Baker Street.  I hurried up the stairs and there I saw him - my oldest and best friend - Sherlock Holmes. We exchanged greetings and then he said "We have a problem,Watson.  The game's afoot." "But Holmes, how can this be?  You were last scene lying on the pavement with blood streaming from your lifeless body after falling from a very tall building."
"Precisely, Watson.  That is the problem and a three pipe one at that."
Then he lit his pipe and vanished in a puff of smoke.......

Now I find that Yvette Cooper got a first in PPE at Oxford.  That makes four of them - Cameron, Osborne and Milliband - now it's Mrs Balls as well. Hmmm......