The Silver Citadel

Take telepathic twins separated by kidnap and a female religious leader using her network to smuggle heroin. Add a liberal sprinkling of flamboyant mysticism -- the 'Old Gods' against whom the twins and three other children must battle in order to save the world. Extend the story into three books and you have a firm foothold in the potboiler market. There are many other writers doing far more positive and creative things in this genre -- for example, Peter Dickinson in his trilogy 'The Changes' of which I'd particularly recommend The Devil's Children. buy that, instead.