Children of the Lamp: The Cobra King of Kathmandu by P.B. Kerr

In the third book of the Children of the Lamp series, The Kobra King of Kathmandu by P.B. Kerr, Phillipa and John Gaunt, djinn twins, are off on another adventure.

Their friend, Buck, is in trouble. A crazy cobra cult, which has already killed several people, including Buck's friend, is trying to track him down because of a strange picture Buck has from India. In their efforts to help him, the twins, along with their butler Mr. Gronin, travel to India to see what they can track down about this mysterious, sinister cobra cult. But are they in over their heads? And will they end up like all the other people that have gotten in the way of this group and its disgusting leader? (He really is disgusting. He hasn't taken a bath in ages.) Read the book and find out! (While not explicitly shown, this story does contain child death, Buck's friend. Keep that in mind if you are sensitive to such things.)