George Smiley, for one, is a fictional character created by British author John le Carre. He is a retired British intelligence officer and master SPY who appears in many of le Carre's novels. He is best known for his role as the head of the British Secret Intelligence Service (MI6) and as the leader of a team of spies in the Cold War. He is also known for his skill in espionage and counter-espionage. The term 'spymaster' is used to describe someone who is in charge of a team of spies, and the term 'SPY' is used to describe someone who is engaged in espionage activities.