What significant event occurs at the beginning of the book that drastically changes the Greystone children's lives?
Their mother is arrested for a crime she didn't commit.
Their mother is kidnapped by mysterious strangers.
Their mother wins a lottery and buys a new house.
Their mother leaves on a sudden, secret business trip.
What were the names of the three Greystone children?
Alex, Beth, and David
Chess, Emma, and Finn
Matt, Sara, and Peter
Devin, Ella, and Toby
What unusual item do the children find that leads them to suspect their mother's disappearance is connected to the news report about the kidnapped children?
A strange set of coded puzzles
A cryptic handwritten map
A hidden safe full of money
Three identical school ID cards
Who is the woman who comes to stay with the Greystone children after their mother disappears?
A close family friend, Aunt Laura
Their mother's colleague, Ms. Lylburn
A distant relative, Mrs. Morales
Their maternal grandmother, Mrs. Willow
What does the oldest Greystone child, Chess, initially decide to do with the cryptic clues their mother left behind?
Hide them from his siblings.
Treat them as a game and try to solve them with his siblings.
Throw them away, believing they are a distraction.
Immediately go to the police.
What is the name of the place their mother repeatedly warns them not to go?
The Hidden Staircase
The Whispering Woods
The Blue Window
The Old Mill
What unique characteristic do the kidnapped children in the news report share with the Greystone children's own mother?
They share the same birthday.
They have the same unusual middle name.
They have matching birthmarks.
They all love the same obscure poem.
What is the primary danger associated with the place the children must go to find their mother?
It's a secret government testing facility.
It's guarded by fierce dogs.
It's a parallel world where they are the "strangers."
It's a ruined building that is structurally unsafe.
The codes, riddles, and instructions left by their mother are primarily intended to help the children do what?
Find the family's hidden fortune.
Follow a path that will lead them to the parallel world.
Figure out how to contact the police without being overheard.
Decipher the final location of the kidnapped children's parents.
The conclusion of the book reveals that the three kidnapped children are actually...
actors hired to create a distraction.
their cousins from a foreign country.
their mother's siblings who were separated at birth.