In Amber: a romance

The king has been murdered. The same fate as her father's was plainly intended for the eleven-year-old princess, Idomela, but friends contrived to rescue and deftly vanish her.

The usurper, Corvan is on the point of establishing as legal fact, the extinction of the proper ruling house, hence his own lawful succession.

If Idolema, has indeed lived on - the ever more distasteful rule of Corvan would persuade her allies that her reappearance offers the last chance for restoration of the less onerous government of her father's day.