A teenage girl on the Quirinal dies after taking what is described as a love potion. Albia is drawn into the case by her husband's former wife and begins tracing the mixture to Pandora, a herbalist whose beauty business serves a secretive local clientele.
The investigation reveals sexual rivalries, concealed relationships and conflict among neighbourhood gangs. When another person close to the inquiry is killed, Albia must distinguish dangerous superstition from the more deliberate uses of poison and intimidation.