The shadow of the man in black has followed fourteen-year-old Amy Cahill and her younger brother Dan on their worldwide search for 39 Clues that lead to a great power. The man has tried to kill them and he is a Madrigal, as were their parents. And now the man is ready to step out of the darkness for their final confrontation.

"Why would Quentin Herms flee into the Quag? There was nothing in the Quag except certain death. Vega Jane has never left the village of Wormwood. But this isn't unusual--nobody has ever left the village of Wormwood. At least not until Quentin Herms vanishes into the unknown. Vega knows Quentin didn't just leave--he was chased. And he's left behind a very dangerous trail of clues that only she can decode. The Quag is a dark forest filled with terrifying...

An adventure on the wide open ocean, and Ruby is all at sea. Can she crack the case while evading the clutches of the evil Count von Viscount? Well, you wouldn't want to bet against her.

"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 to a terrible...

"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...

Thirteen-year-olds Bertie Bradshaw of London and American Eleanor Shea team up to decipher a coded notebook and stop a double agent from revealing secrets about the upcoming D-Day invasion.

"Could the Mark Twain books hidden through Book Scavenger contain clues about the string of recent arson fires plaguing the city? And will Emily and James uncover the mystery before the arsonist comes after them?" -- Provided by publisher.

"¿Qué pasaría si descubrieras que tu familia es una de las más poderosas de toda del historia de la humanidad? ¿Y si te dijeran que la fuente de poder de la familia está escondida por todo el mundo en forma de 39 pistas? ¿Y si, además, te dieran a elegir entre tener un millón de dolares... o conseguir la primera de las pistas? Si fueras Amy y Dan Cahill, ¡escogerías la pista y emperazarías una carrera muy peligrosa!" --From publisher's...

A million dollars, or a clue? Police report a break-in at an elite hotel, and the suspects sound suspiciously like Amy and Dan. There's a car and speedboat chase and an angry mob! When there's a Clue on the line, anything can happen. "La carrera contrarreloj para encontrar las 39 pistas ha empezado, y los hermanos huérfanos Amy y Dan Cahill no pueden creer que estén a la cabeza de la búsqueda, que los lleva a Viena y Venecia. Pero, ¿lograrán...

"Billie B. Brown y Jack, su mejor amigo, encuentran un extraño mensaje en clave en la puerta de al casa de Billie B. Con esa carta se abre una cadena de códigos secretos que los cuatro miembros de El Club del Misterio deberán descifrar para saber qué ocurre. ¿Quien les manda esas enigmáticas cartas? ¿Se tratará de un peligroso caso de espionaje? Billie B., Jack, Mika y Alex tenderán que aguzar su ingenio más que nunca."--page 4 of cover. Billie...