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This article contains plot details about an upcoming episode.
The group then goes to a train station according to a lead and Dan nearly gets hit by a train. However, Alistair pulls both Dan and Amy into the room saving them both. In this room, they find a haiku, which tells them to use geometry to find Hideyoshi's treasure. Later, they find some geometric shapes, but are chased by the Yakuza and are once again nearly killed. They are rescued by Nellie, who has struck a deal with, and is accompanied by, the Kabras. When the Kabras give Amy and Dan a small coin of importance to the search, the two Cahills agree to join forces with the Kabras. They decode another message in the shapes, and some English letters. The message tells them to go to Korea.
In Korea, everyone goes to Alistair's house. There, they look at old books about the Cahill family in Alistair's secret library. By reading one of them, Amy and Dan figure out that the secret of the 39 Clues is the secret to alchemy, shown on a chart they see:
They also figure out that they should go to a mountain called Pukhansan.
On the mountain, they find an entrance, and open it with the coin they have. Inside, they find all of Hideyoshi's treasure, and the third clue, gold. The Kabras have a plan, but little do they know that Dan also has a plan. He discovers an anagram and says the next location is Lake Tash, Kyrgyzstan. The Kabras then betray them and block them inside the cave. Dan then tells Amy that he tricked the Kabras into thinking that Lake Tash was the next location, and the two figure out that it's actually an anagram for the words, Al Sakhet and Alkahest, the alchemical word for the philosopher's stone. Dan and Amy make it out but Alistair appears to be crushed under falling rocks. They also see Bae Oh talking about this with The Man in Black. Upon returning to Alistair's estate, Dan sees Alistair's gloves (which he was wearing before the cave in), and realizes that he isn't dead. They also figure out that the next clue is in Egypt. The adventure continues inBeyond the Grave. The book ends with Bae Oh, sitting his office. He pages his secretary but Alistair answers instead. Alistair threatens his uncle, and when Bae looks in his receiving room, no one is there.
With a secret of this much power, jealousies were inevitable and no alliances would survive.
-Irina Spasky thinking during the book. pg 3
"A DEADLY ALLIANCE
There's only one rule in the race to find 39 Clues hidden around the world.TRUST NO ONE. But when the hunt leads fourteen-year-old Amy Cahill and her younger brother, Dan, to Japan, their only chance to find the third Clue seems to lie with their unreliable uncle, Alistair Oh. Will they be foolish enough to make an alliance? With a Clue on the line, Amy and Dan might not have a choice. But in the Cahill family, trusting your relatives can get you killed...."
- [[The Holt Family]]
- [[Irina Spasky]]
- [[Man in Black]]
The competition is about Hope.
The key is on one of the blades on the inside front cover.
To: The Cahill Family
Regarding: The Last Will and Testament of Grace Cahill
This letter is to inform you that you have been named in the will of the late Grace Cahill. Your inheritance from Grace Cahill is not gold, jewels, or money. Instead, it is a staggering opportunity - the chance to join the hunt for the 39 Clues.
You have never been told, but you are a member of the Cahill family - the most powerful family the world has ever known. 39 Clues lead to the source of the Cahill family's power, and the person to find them will receive a reward beyond measure.
The Clue hunt is on, and there is over $100,000 in prizes up for grabs.
Good luck. You're going to need it.