The end of the line.
"We can't stop her. It's just Dan and me against the most evil woman in the world."
— Amy Cahill's thoughts
Into the Gauntlet is the tenth and final book in the first series of The 39 Clues. Although the next book, Vespers Rising, is listed as the actual last book in the first series, that only serves as a link between the first and second series.
Fourteen-year-old Amy Cahill and her younger brother, Dan, have had enough. Not only do they have to find the 39 Clues first, they're expected to reunite their backstabbing family - the same people who killed their parents. But Amy and Dan haven't survived explosions and assassination attempts for nothing. They have a plan to finish the Clue hunt on their own terms. Too bad there's a final, fatal secret the Madrigals haven't told them. A secret that could cost Amy and Dan - and the world - everything...
Tropes:
- Back for the Finale: In contrast to the previous book, which only featured two clue-hunting teams, all surviving teams come back for the last book.
- Chekhov's Skill: At first, Jonah's love of Shakespeare seems to have only been thrown in to show that Jonah has Hidden Depths, instead of just being a Jive Turkey and Teen Idol. It turns out that a knowledge of Shakespeare's lost plays is required to reach the end of the gauntlet and find the final clue.
- Continuity Cavalcade: The questions in the final gauntlet are practically this, from the previous nine books.What was Mozart's sister's name?
Who was Shaka Zulu?
Why does a Mobius strip seem impossible?
Of the small number of female pharaohs in ancient Egypt, which one had the longest reign?
As a printer, Benjamin Franklin could order large amounts of this substance without raising suspicions. But Clue hunters who followed him know that he was actually trying to replicate the work of his ancestor Gideon Cahill. What is this ingredient? - Enemy Mine: Amy and Dan, Hamilton, Alistair, Jonah, Ian and Natalie and Sinead are forced to complete the gauntlet together, as it requires a person from each family branch to do so. When they arrive at the room with the last Clue, everyone scrambles to reach it first, showcasing the alliance quickly falling apart.
- Improvised Weapon: Amy uses the serum vial as a makeshift club to knock Isabel unconscious, as it was the closest thing she could grab. It ends up breaking in her hands as she does so.
- Reconcile the Bitter Foes: Amy and Dan struggle through doing this, with the both of them deciding they need to obtain the last Clue for this to happen. Eventually, they succeed in this, without doing the latter.
- The Reveal:
- During the Romeo and Juliet play, a bunch of masked people who find the next hint are revealed to be the Starling triplets from The Maze of Bones, having recovered from the Franklin Institute bombing.
- The final Clue isn't a substance or metal of some kind. It's the formula to combine the other Clues into a serum that that will imbue the drinker with all four branches' traits.
- William McIntyre tells Amy and Dan that the real reasons for the Cahill family's reunion was that they can work together to defeat another family who are also after the Clues. When the codes in this book are solved, it reveals them to be called the Vespers."They make [Isabel Kabra] look like Mother Teresa."
- Wham Line: Many.
- To gain Alistair's trust, Sinead reveals this:"There's something else you might want to know. We stole Bae Oh's Clues!"
- When Isabel is threatening the safety of Ned and Ted for Sinead's Clues:Sinead: Which brother did you find hiding in my aircraft? I can't quite tell...
Isabel Why — do you love one brother more than the other? Which cripple do you prefer? - If the codes in the pages and last page are solved, they form two unnerving sentences that hint at the second series.The Cahills aren't the only ones looking for the Clues. The Vespers are coming.
- To gain Alistair's trust, Sinead reveals this:
- You Wouldn't Shoot Me: Ian tells Isabel that he doesn't believe that she would shoot her own daughter, Natalie. She doesn't... by shooting Natalie in the foot.
