What would you do if you were asked to choose one of two options in a will left by an extremely rich aunt? One million dollars on the spot or the chance to go on a treasure hunt where failure could mean death? Amy and Dan Cahill choose the latter. And there starts Rick Riordan’s (he’s the creator of the Percy Jackson series) hugely entertaining fantasy thriller, The 39 Clues.

This is Book One of The Maze of Bones series. When Grace Cahill dies, her lawyer William McIntyre summons the entire Cahill family for the funeral. It’s a family that lies scattered across the globe, from Korea to Venezuela. After the funeral, a select few are called in for the reading of Grace’s will.

The lawyer gives them the option. He asks those seated to make a choice. Pick up the envelope stuck under the chair that holds the key to a million dollars or wait for him to give them a clue that will “unlock" the Cahill treasure — after a hunt. Only one team or individual, announces the lawyer, can find it.

There is a history to the Cahill family: “The Cahills have a greater impact on human civilization than any other family on Earth," says Grace in a video recording screened for those present. The person who plays the game and finds the secret will become the most powerful and influential one in the world. Or they will die trying.

As it turns out, Amy and Dan are not the only adventurous Cahills in the family. Besides the brother-sister duo, six other teams stake their claim to the treasure. The others are the Kabra siblings (Ian and Natalie), the Starling triplets, Alistair Oh, Irina Spasky, the Holt family and Jonah Wizard (a TV star).

McIntyre unleashes a card that has the first clue. “Resolution: The fine print to guess, Seek out Richard S…"

Nonplussed for a while, the contestants put their heads together. Dan and Amy hit upon the meaning and it leads them to Aunt Grace’s hidden library and the works of Benjamin Franklin (he was a Cahill too, goes the story). Alistair Oh offers to help them since they would find it difficult to move ahead without the help of an adult. Also, he points out, the search could take them around the world.

The first quick discovery almost results in the brother and sister losing their lives as the house catches fire and is burnt down. Amy and Dan manage to escape but observe a grey-haired man in a suit watching them. The man becomes a constant tail on their quest that takes them from Boston to Paris and its catacombs. Helped by their nanny, Nellie, and fighting off numerous challengers, the two have a dangerously rollicking ride on their way to unravelling clue No. 2. Can they always remain one step ahead of the competition, which has a disconcerting way of arriving when Amy and Dan make their discoveries?

The 39 Clues doesn’t just let you be a reader. It wants you to be part of the action. Riordan has made it an interactive experience. Amy and Dan’s competition is you, and not just the Cahill family, says the blurb on the book. Puzzled? There are books and cards (with clues) that you can collect in each book and there is a website (The39clues.com) where you can play the game.

Read the books, collect the cards and play the game. Riordan is sure to get his audience; it’s a fun ride — and Book Two will be much awaited.

The writer is the editor of Heek, a children’s magazine.

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