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.

The second installment of Bernard Cornwell's New York Times bestselling series chronicling the epic saga of the making of England-the basis for The Last Kingdom, the hit television series. As the last unvanquished piece of England, Wessex is eyed hungrily by the fearsome Viking conquerors. Uhtred, a dispossessed young nobleman, is tied to the imperiled land by birth and marriage but was raised by the Danish invaders-and he questions where his allegiance...

Now chief and ruler of Berk alongside Astrid, Hiccup has created a gloriously chaotic dragon utopia. When the sudden appearance of female Light Fury coincides with the darkest threat their village has ever faced, Hiccup and Toothless must leave the only home they've known, and journey to a hidden world thought only to exist in myth. As their true destines are revealed, dragon and rider will fight together-to the very ends of the Earth-to protect everything...

While Astrid, Snotlout and the rest of the gang are challenging each other to dragon races, Hiccup and Toothless journey through the skies, charting unmapped territories and exploring new worlds. When one of their adventures leads to the discovery of a secret ice cave that is home to hundreds of new wild dragons and the mysterious Dragon Rider, the two friends find themselves at the center of a battle to protect the peace.

Follows young warrior and outsider Uhtred on a fierce mission to reclaim his birthright, retelling the history of King Alfred the Great and his desire to unite the many separate kingdoms into what would become England.