This is the third book in the trilogy of the 100 cupboards.
It is amazingly written, and has a great ending.
The book goes like this:
In The Chestnut King, Henry's Aunt Dotty, Uncle Frank and
cousins from Kansas now live in Badon Hill, as well. Nimiane continues
to stalk Henry. She wants his blood, as it will increase her power. The
scar she previously inflicted on his face continues to grow and rot.
Henry's father, Mordecai, fears the wound will kill Henry unless they
can destroy the undying witch-queen soon.
Soldiers sent by the emperor of this world demand that Mordecai come
with them across the sea. The emperor wants Mordecai to answer to
charges that his family helped free Nimiane. Mordecai is more concerned
about destroying the witch-queen and saving his son than his defense. He
says he will respond to the emperor once he has completed his mission.
He leaves for Endor, where Nimiane resides.
In response to Mordecai's disobedience to the emperor, the soldiers
capture his family, including Uncle Frank, Henry's mom and his cousins.
Then they set fire to the family's house, leaving Henry's cousin
Henrietta and grandmother inside. Henry helps his grandmother and
Henrietta escape through a cupboard portal that takes them back to
Kansas. There, they enlist the help of Henry's baseball buddy, Zeke.
Leaving Henry's grandmother with Zeke's mom, the three children travel
through the cupboard leading to Endor.
The kids find themselves in a crypt with Nimiane's relative, a
shape-shifting creature called Nimroth (or Blackstar). Nimiane has 10
henchmen, whom she controls with her mind. They're called fingerlings
because they have fingers attached to the back of their heads. Coradin,
the lead fingerling, follows Henry on his journeys through various
worlds. Coradin and the fingerlings pursue the children through the
underground tombs of Endor until Henry helps Zeke and Henrietta return
to the attic in Kansas. Henry returns to Endor, finds his father and
Uncle Caleb, gathers old manuscripts that may help them find the
witch-queen's secrets and transports the papers back to Kansas.
Back in Badon Hill, Fat Frank — an incompetent fairy who has actually
been stripped of his fairyhood — rescues three of the children in
Henry's family. A group of fairies locates Frank and takes him and the
children to the Chestnut King so Frank can answer for his un-fairylike
conduct. Meanwhile, Uncle Frank and the other captured family members
find themselves on a rough and unpleasant sea voyage.
Henry finds entry into the fairy world, where he seeks the help of the
Chestnut King. The king makes a bargain with him: He will help Henry
save his family and vanquish the witch-queen if Henry will take over as
Chestnut King. Feeling cornered, Henry agrees. Henry is reunited with
the family members that were with Fat Frank. Coradin and the
witch-queen's other henchmen capture Uncle Frank's group, forcing Henry
to confront Nimiane in her throne room. Henry disables the witch-queen
just before she would have destroyed Henry and his loved ones. Instead
of becoming the king himself, Henry makes Fat Frank the new Chestnut