Fourteen-year-old Amy Cahill and her younger brother, Dan, head to the Land Down Under to discover what their own mother and father knew about the hunt for the 39 Clues. But following in their parents' footsteps brings up lost memories for Amy so awful that she can't share them . . . even with Dan. Haunted by the ghosts of their past, chased by deadly competitors, Dan and Amy can't see who is an enemy and who is a friend. Their blindness leads

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Amy and Dan are hot on the trail of the fourth Clue, but their ruthless relatives will stop at nothing to eliminate them from the competition. Their hunt leads them to an ancient city that has been a hot bed of Cahill activity for centuries. The clock is ticking for Amy and Dan. Includes six game cards. Consumable. Amy and Dan are hot on the trail of the fourth Clue, but their ruthless relatives will stop at nothing to eliminate them from the competition....

When their latest jewel heist goes wrong, March and Jules end up with one of three cursed jewels, and the only way they can break the curse is to elude the authorities and international criminals to find the other two jewels and reunite them.

March and Jules are teenage twins, following in their father's footsteps as jewel thieves, but when their latest job goes wrong they end up with one jewel, a sapphire called the Morning Star, one of three cursed jewels--and the only way they can break the curse is to elude the FBI, Interpol, and a gang of international criminals, find the other two jewels, and reunite them.