Photo: Courtesy of HBO

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Game of Thrones (HBO, 2011–present)
Factions vie to rule Westeros, fantastical realm replete with dragons, sorcery, shape-shifting, gratuitous female nudity; series most closely follows Stark family's bid for dominance.

Utter ruthlessness of both characters and writers. Beloved protagonists killed off with abandon; guys bad and good commit heinous acts (patricide, regicide, castration). No one safe, nothing sacred.

Cultural Touchstone
"Winter is coming" catchphrase refers to long-foreshadowed arrival of dark times, thanks to frigid weather, zombies who thrive in cold.

One to Watch
"Baelor" (season 1) finds hero Ned Stark desperate to evade execution. Allies race to intervene. Crunch time finally arrives, and—well, let's just say series forcefully establishes disregard for dramatic convention.