Mary Russell is well used to dark secrets - her own, and those of her famous partner and husband, Sherlock Holmes. Trust is a thing slowly given, but over the course of a decade together, the two have forged an indissoluble bond. But what of the other person Mary Russell has opened her heart to, that third member of the Holmes household: Mrs Hudson? Blood on the floor, a token on the mantelpiece, the smell of gunshot in the air: all point directly at Clara Hudson - or rather, at Clarissa, the woman she was before Baker Street. The key to Russell's sacrifice lies in Mrs Hudson's past, and to uncover the crime, a frantic Sherlock Holmes must put aside his anguish and push deep into his housekeeper's secrets, to a time before her disguise was assumed, before her crimes were buried away. There is death here, and murder, and trust betrayed.