Twelve-year-old twins Philippa and John have more adventures when they become involved in an international adventure involving the Blue Djinn, the supreme arbiter of all Djinn.

After getting help for their father, who is cursed with rapid aging, twelve-year-old djinn twins John and Philippa and friends travel through the spirit world in search of Faustina, the only one who can keep their mother from becoming the Blue Djinn, and discover a link to museum thefts and hauntings throughout the word.

Fourteen-year-old djinn twins John and Philippa travel from the Himalayas to Yellowstone National Park seeking to uncover and protect five holy men before the wicked djinn responsible for upsetting the balance of the world's luck finds them.