It is the third in a quintet of novels covering the Arthurian legend, preceded by The Hollow Hills and succeeded by The Wicked Day.

Having taken Morgause (unaware that she was his half-sister) to his bed as a very young man after his first battle and victory, Arthur is now the father of Mordred.

He spends a great deal of time traveling in disguise and observing Morgause's scheming and intrigue.

When she first appears she is disguised as a boy, and Merlin initially takes her for the reincarnation of a child he had seen some years before whom he would have chosen as apprentice, but who died unexpectedly.

He escapes after a few weeks, through a combination of chance luck and ingenious planning, and travels incognito to let Arthur know he is still alive.