根据一次电影或电视节目的描述，撰写一篇有关剧情的简短总结，包括主要角色。
作品：Game of Thrones

角色：Jon Snow, Daenerys Targaryen, Cersei Lannister, Arya Stark
Game of Thrones is a fantasy drama centered around the fight for power over the Seven Kingdoms of Westeros. Jon Snow, a bastard son of Ned Stark, joins the Night's Watch while Daenerys Targaryen, is determined to take back her father's throne with the help of her dragons. Meanwhile, Cersei Lannister schemes to hold onto her grasp on the Iron Throne as Arya Stark seeks revenge for her family. Their paths intertwine as alliances are made and betrayal lurks around every corner.