While staying at the Crooked House, the family home of their housekeeper Mrs. McGregor, the Aldens try to solve a riddle that will lead them to a hidden treasure.

When their beloved aunt--matriarch of the world's most powerful family--dies, orphaned siblings Amy and Dan Cahill compete with less honorable Cahill descendants in a race around the world to find cryptic clues to a mysterious fortune. Includes game cards which the reader may use to play an online version of the treasure hunt.

A sequel to Voyage of the Frostheart finds Ash and his ragtag crew of misfits boarding the Frostheart sleigh to the dazzling city of Aurora, where he practices the art of songweaving while searching landmarks for clues about his long-lost parents.

"When a tragic accident takes the life of the only family she's ever known, [17]-year-old Raven is sent to New Orleans to start over. She soon discovers that she can hear the thoughts of others around her--and another, more disturbing, voice in her head"--

Six-year-old Gretl Schmidt is on a train bound for Auschwitz. Jakób Kowalski is planting a bomb on the tracks.

As World War II draws to a close, Jakób fights with the Polish resistance against the crushing forces of Germany and Russia. They intend to destroy a German troop transport, but Gretl's unscheduled train reaches the bomb first.

Gretl is the only survivor. Though spared from the concentration camp,

...

I am the girl manny loves. the girl who writes our story in the book of flying. i am alice. Alice is fifteen, with hair as red as fire and skin as pale as bone. Something inside Alice is broken: she remembers words, but struggles to speak them. Still, Alice knows that words are for sharing, so she pins them to posters in tucked-away places: railway waiting rooms, fish-and-chips shops, quiet corners. Manny is sixteen, with a scar from shoulder to elbow....

The Alden children have another mystery to solve when they visit a castle and must figure out which of the guests has stolen the Stradivarius violin.

"In the near future, seniors Lydia and Billy form an unlikely friendship when their high schools are merged, bonding over their Washington town's weird history and their unusual families"--

Having lost his mother and his hearing in a short time, twelve-year-old Ben leaves his Minnesota home in 1977 to seek the father he never knew in New York City, and meets there Rose, who is also longing for something missing from her life. Ben's story is told in words; Rose's in pictures.

"Grace is the last matriarch of the Cahills, the world's most powerful family. Everyone from Marie Curie to Harry Houdini is related to the Cahills, yet the source of the family's 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 the clues race is on, and siblings Amy and Dan must decide what's important: hunting clues or uncovering what really happened to their parents."--...