Writing about the first book, a critic Matt Berman stated, "Like many other adult novelists trying to make the transition, [Kerr] will need to learn that different rules apply – the pacing is different, and kids prefer warm passion to cool detachment.
From New York to Egypt to London, the twins' adventures are filled with excitement as they undergo training in the use of their newly discovered powers but are also fraught with danger as they battle the evil Ifrit tribe of djinn and its leader, Iblis.
Now the mystery surrounding a powerful book of djinn magic named Solomon's Grimoire lures the twins straight into their next extraordinary adventure.
They travel across the globe, from New York City to Istanbul, Berlin to Budapest, but little do they know, a trap has been set and the djinn twins are about to walk right into it.
Fiery magic in a land of ice, midnight intruders, and murder by snakebite sweep John and Philippa Gaunt into their third fantastic adventure.
The Day of the Djinn Warriors is the fourth novel and deals with a race against time for John and Philippa Gaunt to outwit the wicked Iblis.
John and Philippa attempt to rescue their mother from her fate as the Blue Djinn of Babylon and discover that an aging curse has been placed on their father and if the twins are gone too long, he will rapidly become an old man.
As the twins and their friends travel around the globe on their rescue mission, they notice an evil force has awakened the terracotta warriors created by an ancient Chinese emperor, and someone with very bad intentions has cast a spell possessing the soldiers with wicked spirits.
John and Philippa Gaunt find themselves tangled up in a spellbinding mystery that takes them deep into the heart of the Amazon jungle.
When a collection of Incan artifacts goes missing, the Blue Djinn of Babylon dispatches the twins and Uncle Nimrod to recover them.
As volcanoes begin erupting all over the world, spilling golden lava, the twins must go on a hunt for the wicked djinn who wants to rob the grave of the great Genghis Khan.
Nimrod Plantagenet Godwin is the powerful djinn uncle of John and Philippa and de facto leader of the Marid.
He feels more at home in his lamp than outside of it, following a long period of forced confinement in a milk bottle thanks to a djinn from the Ghul tribe.
Layla Gaunt is an extremely tall and glamorous woman, the eccentric mother of John and Philippa, and sister to Nimrod.
She had cut herself off from the djinn world, including dropping the use of her powers right after turning her husband's murderous brothers into pet dogs.
She finally began using her powers again to turn an assassin, hired to kill John and Phillipa, into a cat, who they took in as a pet and named Monty.
During the end of the third book he becomes a victim of the Methuselah Binding (which causes him to age several years), cast by Layla Gaunt to prevent John and Philipa from attempting to stop her from being the next Blue Djinn after Ayesha.
Marid Jinn Jann Ifrit Shaitan Ghul In 2007 DreamWorks acquired the rights for a film adaptation to be produced by Nina Jacobson.