Once she was a powerful Djinn. Then Cassiel defied her ruler, Ashan, who tore her very essence away and reshaped her in human flesh as punishment. Forced to live among mortals, Cassiel has found refuge among the Weather Wardens – whose powers she must tap into regularly, or she will die.
Cassiel earns her keep by assisting the Earth Warden Manny Rocha on his missions – which she finds much easier than coping with the emotions and frailties of her human condition, especially her growing affection for Manny's brother, Luis. But when Cassiel encounters a malevolent force that threatens the Rocha family, she discovers that her perceived human weaknesses may be her greatest strengths . . .