The 39 clues. Main series

Minutes before she died Grace Cahill changed her will, leaving her descendants an impossible decision: "You have a choice - one million dollars or a clue." Grace is the last matriarch of the Cahills, the world's most powerful family. Everyone from Napoleon to Houdini is related to the Cahills, yet the source of the family power is lost. 39 clues hidden around the world will reveal the family's secret, but no one has been able to assemble them. Now...

"Amy and Dan Cahill have been located once again, this time in the company of the notoriously unreliable Alistair Oh. Could they have been foolish enough to make an alliance? Spies report that Amy and Dan seem to be tracking the life of one of the most powerful fighters the world has ever known. If this fearsome warrior was a Cahill, his secrets are sure to be well-guarded--and the price to uncover them just might be lethal"--Publisher.

"A strange telegram lures fourteen-year-old Amy Cahill and her younger brother, Dan, deep into Russia and away from the only trustworthy adult they know. Signed with the initials NRR, the telegram launches a race to uncover a treasure stolen by the Nazis and the truth behind the murder of the last Russian royal family. All too soon, the treasure hunt starts to smell like a Lucian trap. But the bait might just be irresistible--what will Amy and Dan...

The most dangerous secret in Amy and Dan's past is unveiled in Book 7 of the #1 New York Times bestselling series.

The hunt for 39 hidden Clues that lead to an unimaginable power have taken a heavy toll on fourteen-year-old Amy Cahill and her younger brother, Dan. They've just seen a woman die. They're wanted by the Indonesian police. They're trapped on an island with a man who knows too much about the death of their parents. And a tropical...

Throughout the hunt for the 39 Clues, Amy and Dan have encountered some of the darkest aspects of history... and had to deal with the role their family played. But are they ready for the truth? In this thrilling ninth installment, Amy and Dan hit the high seas as they follow the trail of some infamous ancestors to track down a long lost treasure. However, the real prize isn't hidden in a chest. It's the discovery of the Madrigals' most dangerous secret...

The Cahills aren't the only family searching for the Clues. . . .The Cahills thought they were the most powerful family the world had ever known. They thought they were the only ones who knew about Gideon Cahill and his Clues. The Cahills were wrong. Powerful enemies -the Vespers- have been waiting in the shadows. Now it's their time to rise and the world will never be the same. In Vespers Rising, a brand new 39 Clues novel, bestselling authors Rick...