Cleo and Evan have a secret. A collection of books so dangerous they are locked up tight. A friend has vanished inside the pages of one of them. It's up to them to find the key that will set her free. A PRICELESS DIAMOND...STOLEN! When Cleo and Evan go undercover to help a rookie detective interview a mansion full of suspects, nothing is as it seems. They must catch the crook—and find the right key—or they could be trapped inside this mystery forever...

Getting lost in a good book has never been this dangerous! Cleo and Evan have a secret. A collection of books so dangerous they are locked up tight. A friend has vanished inside the pages of one of them. It's up to them to find the key that will set her free. A SPY MUST BE READY FOR ANYTHING!Agents Cleo and Evan have been given an impossible become super-spies and foil the plans of an evil mastermind. But it won't be easy to break into the Viper's secret underwater lair, complete a daring rescue, find the right key, and get out alive!

Getting lost in a good book has never been this dangerous! Cleo and Evan have a secret. A collection of books so dangerous they are locked up tight. A friend has vanished inside the pages of one of them. It's up to them to find the key that will set her free. THE CURSE OF THE FULL MOON MUST BE BROKEN!On a dark and stormy night, Cleo and Evan are haunted by a disaster. Evan has been bitten by a werewolf! If they can't find the cure—and the right key—before the full moon rises, he'll be stuck prowling the pages of this ghost story for good!

Getting lost in a good book has never been this dangerous! Cleo and Evan have a secret. A collection of books so dangerous they are locked up tight. And only they can find the keys to release the magic inside!A FORTUNE LOST AT SEA!When Cleo and Evan set sail on the Titanic, time is not on their side! The famous ocean liner is destined to hit an iceberg. If they can stop a thief from stealing a priceless jeweled book—and find their next key—they might avoid sinking with the ship in this historic disaster!

Getting lost in a good book has never been this dangerous! Cleo and Evan have a secret. A collection of books so dangerous they are locked up tight. And only they can find the keys to release the magic inside! SURVIVING THE WILDERNESS IS ONLY HALF THE BATTLE! A plane crash in the Amazon lands Cleo and Evan on the hunt for a valuable golden statue. They must find it—and their next key—to make it home alive. But the jungle is full of deadly creatures, raging rapids, and an all-too-familiar villain who wants nothing more than to trap them forever!