It has been a century since Shadea a'Ru's coup d'etat shattered the Third Druid Council, and nearly resulted in the collapse of the Forbidding and the release of the Demons contained within. For decades, Khyber Elessedil has been fighting to save the Druid Order, and fulfill her predecessor, Grianne Ohmsford's, hopes for it. When Druid trainee and Elven Princess Aphenglow Elessedil uncovers evidence that the lost Elfstones of Faerie are somewhere within the Forbidding, Khyber, who has nothing to lose, puts together an expedition to go and find them.
Joining Khyber on this trip are the Ohmsford twins Redden and Railing, and their friend and crush, Mirai Leah, who see the experience as little more than one big adventure. The Forbidding is a dangerous place, however, and Tael Riverine, Straken Lord, and current leader of the Demons, has not forgotten the humiliation that he endured at the hands of the last band of humans to enter his domain. He wants Khyber and the Ohmsfords dead, and there are few lines he won't cross to make sure that happens.
Back in the Four Lands, the situation has also taken a turn for the worse. The Federation, always an enemy of the Elves and the Druids alike, has come under the sway of Edinja Orle, an Evil Sorcerer who wishes to be Prime Minister. Even more troubling is the apparent sickness of the Ellcrys, the tree that maintains the Forbidding and keeps the Demons sealed away from the real world. And as Aphenglow and her sister Arling set out on a journey to create a new Ellcrys, and Edinja Orle interferes for his own reasons, Tael Riverine amasses his legions, with the goal of destroying the intruders, breaking free of the Forbidding, and doing what The Dagda Mor could not—bring the Four Lands under the control of the Demons.
Tropes appearing in this series include:
- Big Bad: Tael Riverine again.
- Big Good: Khyber Elessedil, High Druid of Paranor and leader of the search for the Elfstones.
- Continuity Porn: While most of the Shannara series plays rather relaxed with canon, this trilogy features more cameos, references, and concepts dating back to earlier in the Shannara timeline than any other series. The Word and the Void are reference in ancient journals, Alannon (as a shade) and Amberle (as the Elcrys) and Grianne Ohmsford (as the Witch Wraith) all appear and have lines at various points.
- Demon Lords and Archdevils: The Straken Lords, now united under Tael Riverine.
- Enemy Mine: The Federation have a long history of picking fights with just about anyone in the Four Lands, but the stragglers who survive the Demons' first siege head for Arborlon to assist the Elves in the coming invasion.
- Evil Sorcerer: Both Edinja Orle and Demon Lord Tael Riverine.
- Evil vs. Evil: The Witch Wraith the haggard but wildly powerful remains of Grianne Ohmsford vs Straken Lord Tael Riverine.
- The Federation: Still The Empire in disguise, still the main antagonist faction.
- Happy Ending Override: After finally finding a place in the world she could be at peace within the Tanequil, Grianne Ohmsford is dragged back from the brink of death to settle her score with Tael Riverine. The bitterness she feels at this is such that it reverts her to her hateful, destructive Ilse Witch personality, and she would have personally seen the Four Lands destroyed if the restoration of the Elcrys didn't trap her in the Forbidding.
- Intimidation Demonstration: Tael Riverine sets up his fight with Khyber to reaffirm to the Jarka Ruus why he's the top dog in all of the Forbidding. Khyber puts up a worthy fight and even gets the upper hand, but Riverine giving her a slow-acting poison, unfortunately, assures his victory.
- The Legions of Hell: The third attempt by the Demons to break out of the Forbidding, and the second time that they actually pull it off.
- President Evil: Edinja Orle, like Sen Dunsidan before her, is a very bad politician who isn't adverse to abusing dark magic for herown gain. The difference is that Orle has her own magic, while Dunsidan was dependent on the Ilse Witch and The Morgawr.
- Punch-Clock Villain: The members of the Federation's military are depicted as particularly sympathetic in Witch Wraith, willing to take Edinja Orle's morally questionable orders up to a point, but shifting all focus to protecting one another and innocents once the demon invasion gets going.
- The Remnant: Khyber Elessedil's Fourth Druid Council is a shadow of the Third, which was torn apart by Shadea a'Ru.
- The Savage South: The Southland Federation is still a xenophobic expansionist state ruled by some very bad men.
- Science Fantasy: As evidenced by the increasing industrialization of the world, and especially The Federation/
- Sibling Triangle: Redden and Railing are both in love with Mirai Leah.
- Wizard Duel: The trilogy concludes with one between the Witch-Wraith and Tael Riverine to see who will lead the Demons.