Mycroft and Sherlock

When a ship carrying cargo belonging to Mycroft's best friend Cyrus Douglas runs aground, Mycroft persuades Sherlock to serve as a tutor at the orphanage that Douglas runs as a charity, so that Douglas might travel to see what can be salvaged. When a boy dies of a suspected drug overdose Sherlock decides to investigate, following a trail of strange subterranean symbols to London's squalid opium dens. Meanwhile a meeting with a beautiful Chinese woman leads Mycroft to the very same mystery, one that forces him to examine the underbelly of the opium trade that is enriching his beloved Britain's coffers.