Emily Lawrence knows it isn't easy being the first — and so far, only — woman detective in late 19th century Washington DC. With the support of Charles, her husband and business partner, and her own talent for observation and scientific research, Emily tackles the most baffling cases, helping the police solve robberies, kidnappings, and even murder.

Although the work is exciting, it's also dangerous; Emily and Charles must balance their pursuit for the truth with the desire to protect each other. As she gains skills and experience, Emily discovers that the investigations closest to home are often the most challenging.