When their picture-perfect Cotswold village family life with a perpetually young father and hippy mother is shattered by a tragic Easter weekend, four siblings pursue separate adult lives before a reunion reveals astonishing truths.

Conspiracy: Harper Winston's brother has disappeared. Pursuing his dream of sailing the Caribbean, Michael hasn't responded to texts or emails in days. When even the Coast Guard can't find him, Harper is forced to take desperate measures. Which means going to Chase Garrett, once her brother's best friend, now the only man she can trust...or so she hopes. As the successful owner of Maximum Security, Chase has learned to trust his gut. He knows Harper's...

When the Alden children help the curator of the Greenfield Museum set up a traveling exhibit of ancient Egyptian artifacts, the display seems to be undergoing a run of bad luck and the children wonder whether it might be under a curse.

As they continue their search for the 39 Clues in China, fourteen-year-old Amy is faced with a terrible dilemma when her eleven-year-old brother Dan suddenly disappears--keep on searching for the next Clue or try to find her brother.

When the Alden children go camping on Blizzard Mountain, a place said to be inhabited by a ghost looking for buried treasure, they begin to think someone or something is trying to scare them off.

Amy and Dan Cahill are no strangers to impossible tasks. After seven of their relatives were kidnapped, the siblings scoured Europe for the priceless artifacts Vesper One demanded in exchange for the hostages. But then the Cahill kids are given an assignment that pushes them to their breaking point, a journey to a legendary city. Amy and Dan know they can't afford to fail, yet they're running out of options and running out of time.

Amy and Dan continue their search for the clues and cross oceans amid ruthless enemies and dangerous truths while following the trail of a famous aviator.

The Alden children, isolated in a storm at a small bus station, are led into a mystery centering on a polluted river.

Fourteen-year-old Amy Cahill and her younger brother Dan thought they could return to their regular lives when they found the 39 clues. But the Vespers, powerful enemies, will stop at nothing to get the clues. And with the Vespers rising, the world is in jeopardy.

While exploring the caves around Dragon's Mouth Cavern, a series of unusual and somewhat frightening events convinces the Alden children that someone does not want them around.