Queen Victoria has a little problem: there's a petty thief at work in Buckingham Palace. Mary Quinn takes the simple case, going undercover as a domestic servant. But before long, a scandal threatens to tear apart the Royal Family.
One of the Prince of Wales's irresponsible young friends is killed in disgraceful circumstances. Should the Queen hush things up or allow justice to take its course? Mary's interest in this private matter soon becomes deeply personal: the killer, a drug-addicted Chinese sailor, shares a name with her long-lost father.
Meanwhile, James Easton's engineering firm is repairing the sewers beneath Buckingham Palace. Trouble is, there's a tunnel that's not on the plans. Its purpose is unclear. But it seems to be very much in use.
These overlapping puzzles offer a perfect opportunity for Mary and James to work together again... if they can still trust one another. This is Mary's most personal case yet and she has everything to lose.