Sherlock and the Great Game

Sherlock: "Why are you doing this?" Moriarty: "I like to watch you dance." Sherlock is now facing the biggest challenge of his life. Having placed bombs in various important checkpoints in London, Moriarty is planning to have more than his share of fun. Sherlock has deduced that the checkpoints form a network with the property that it is possible to reach any checkpoint from any other checkpoin