Aliette de Bodard has passed the Angry Robot Test--mix genres, shake but do not stir--by writing an intimate, well-crafted, mystery that fits squarely within the strictures of an English cozy but set in an exotic historical and cultural setting with unique fantasy tropes, arising from Aztec mythology.
Servant of the Underworld (Angry Robot Books 2010), a first-person narrative, features Acatl, a High Priest of Mictlantecuhtli, God of the Underworld and Acatl's patron. Acatl is not a policeman, or a professional crime fighter; instead, he is simply a priest, who has chosen to eschew the heroic life of a warrior like his brother Neutemoc for the quiet life in the Temple, helping the dead make a smooth transition to Mictlan, the underworld. The story begins when Ceyaxochitl, a representative of the Revered Speaker, Ayaxacatl, sends for Acatl to investigate a death where dark magic is evident. Thus Ms de Bodard satisfies one of the first characteristics of the cozy: the detective is an amateur. Acatl is neither a detective nor a warrior; however, the death he has been called to investigate not only concerns Nahual magic but a highly-charge political situation that involves his immediate family. The proximity of the perpetrators is also an element of "cozy" fiction: the mystery usually takes place in a community small enough to make it plausible that the characters know each other and are easily interrogated or examined. Acatl soon learns his brother is the number one suspect and he rapidly tracks the threads of magic through Tenochtitlan in order to prevent his brother's execution.
Cozy mysteries usually have a thematic underpinning based upon the locale of the action or the profession of the protagonist. For instance, in Ellis Peters' series, the medieval world of his detective, Brother Cadfael, forms the thematic underpinning; whereas, in Servant, the mythic magic of the Aztecs and the internecine struggle of the Gods form the major components. The turn of the screw, however, in Ms de Bodard's work is that the Gods are active participants, creating the fantasy elements, and supporting the magical system at work in the novel. Mictlantecuhtli, although a God, is as vibrant a character as our narrator, which sets this cozy squarely within the category of fantasy. It is this use of the mythic that I found most interesting: the magical system based upon glyphs and blood seemed very real and provided a rich, numinous texture to the novel.
Finally, even though Servant involves several murders, the villains perform their gruesome acts off-stage.Acts of violence and explicit sex, although implied, are not visible. Nevertheless, its realistic depiction of magic situate it squarely within the confines of the best historical fantasy. More often than not, magic just is in fantasy novels; in Servant, magic arises naturally from the culture and the historical setting, making this cozy a very satisfying and magical (in every sense of the word) read.