"The Sweetness at the Bottom of the Pie" is a simple mystery, written without explicit violence, sexual situations, or terrorists. The book is filled with humor that is delightful, very tongue-in-cheek and very British. The mystery is solved; its solution is arrived at through intelligent thinking and resourcefulness. The characters are interesting and develop distinct personalities through the course of the story.

Flavia de Luce, heroine of "The Sweetness at the Bottom of the Pie" is an intrepid young lady with a penchant for poisons. Arsenic and its antidotes are her special interests. A brilliant, budding chemist, she is also an all-around persistent protagonist who insists on inserting herself into every situation!

Flavia's family consists of her reclusive, eccentric father and two older sisters, Ophelia and Daphne. Her mother, Harriet, was an adventurer who died tragically during a mountain climbing expedition. Of the three sisters, Flavia believes herself to be most like her mother. The core family is completed by Mrs. Mullet, the cook/housekeeper, and Dogger, a former soldier who served with Mr. deLuce. Having served in a number of positions during his employment with the de Luces, Dogger is now the gardner. He is also Flavia's confidante and mentors her in useful skills such as lockpicking.