The Adventure of the Locked Chamber

Explorer Phillip Peabody has returned from an African safari and is displaying rare artifacts at the Museum. Philomena Pettibone's dog act is performing at the Playhouse. Organ grinder Mario Morelli is getting drunk at the Boar's Head, ranting about the hard times and how he can't make enough money to feed his monkey. Tiny Hoggins, an unemployed jockey, is angered by Mario's complaining and a fight ensues.

At the same time, deep in a high security vault beneath the Bank, an engraver is making his annual inspection of the printing plates for all England's currency.

After forty-five minutes has elapsed, the Bank's head security officer, Colin Battersea, opens the locked vault to find the engraver dead and the plates gone. The grating to the air shaft has been removed, but the shaft itself is far to narrow for a normal man to enter. The engraver certainly would have heard anyone who tried to remove the grating while he was checking the plates.

The coroner believes the victim was poisoned, but he cannot discover how the poison was administered. The Prime Minister himself calls Sherlock Holmes into the case; for if the counterfeiters begin flooding the market with authentic notes, Britain's economy will surely collapse!