Things are heating up in Games of Thrones, or should we say—cooling down? Season 7 seems to be bringing things to a head in every quadrant of Westeros, and the second trailer makes it clear that if anyone wants to survive this season, then they have to band together. It opens with a vision of Sansa Stark, hearing Jon Snow's voice in her head telling her that's where the real battles are fought. There are glimpses of Tyrion and Cersei and, of course, Danaerys in her ancestral home, Dragonstone.
And finally, White Walkers:
Reddit is predictably freaking out and dumping fan theories galore: