As thousands of Viking warriors attack Paris, Sera, Riq, and all the people of the city struggle to defend themselves and Dak remains a prisoner, forced to work for the invading army.

After Jack becomes apprenticed to a Druid bard, he and his little sister Lucy are captured by Viking Berserkers and taken to the home of King Ivar the Boneless and his half-troll queen, leading Jack to undertake a vital quest to Jotunheim, home of the trolls.

Their magic tree house takes Jack and Annie back to a monastery in medieval Ireland, where they try to retrieve a lost book while being menaced by Viking raiders.

In medieval times as various groups of Vikings fight for supremacy of the northern lands and waters, Hallgerd, Gauk, and Hego, three young people from the quiet coastal village of Spjothof, find their fates intertwined as a series of events take them into danger far from home.

"Oh, no! One of the special miceking helmets in miceking chief Sven the Shouter's private collection has been stolen! Could it have been taken by the vilekings -- the rival mouse clan? The micekings journey to the vilekings' village to find out . . . and while they're there, the dragons attack! Can all the mice work together to save their fur?"--Page 4 of cover.

While staying with his grandmother, Harry finds a helmet that magically transports him to a Viking longboat, which he hopes might lead him to his missing grandfather.

Aiden, a novice about to take monastic vows in tenth century Ireland, meets Lana, a girl who understands his ability to hear the sounds of numbers humming from all living things, and just as he is beginning to question his religious calling, the two of them are thrown together in a mission to save their village from invading Vikings.

"This lush tale of magic and dragons is a gem for any adventure-seeking middle grader and perfect for fans of Aru Shah and the End of Time. Anya and the Dragon is the story of fantasy and mayhem in tenth century Eastern Europe, where headstrong eleven-year-old Anya is a daughter of the only Jewish family in her village. When her family's livelihood is threatened by a bigoted magistrate, Anya is lured in by a friendly family of fools, who promise her...

With eighteen-year-old Anne Ross at this side, Cat takes over as captain of the monks' fleet to find the legendary villain known as the Merchant, but they, the pirate hunters, monks, and Commodore Blake, have been betrayed by King George and a once-trusted advisor.

Follows the further adventures and misadventures of Hiccup Horrendous Haddock the Third as his Viking training continues and his father leads a stranger and the Hairy Hooligans to the Isle of Skullions in search of a pirate's treasure.