The most-watched series in HBO history and a worldwide TV phenomenon, Game of Thrones remains a huge runaway hit for the network.  This year, a plethora of compelling storylines will play out to their inevitable, often bloody conclusions.  After the shocking deaths of S4, the season begins with a power vacuum that protagonists across Westeros and Essos look to fill.  At Castle Black, Jon Snow struggles to balance the demands of the Night’s Watch with those of newly-arrived Stannis Baratheon, who styles himself as the rightful king of Westeros.  Meanwhile, Cersei scrabbles to hold on to power in Kings Landing amidst the Tyrells and the rise of a religious group led by the enigmatic High Sparrow, while Jaimie embarks on a secret mission.  Across the Narrow Sea, Arya seeks an old friend while a fugitive Tyrion finds a new cause.  And as danger mounts in Meereen, Daenerys Targaryen finds that her tenuous hold on the city requires some hard sacrifices.