The 'Game of Thrones' star and Jimmy Fallon had his audience thinking she'd dropped a major spoiler from the HBO hit's final season! 'Game of Thrones' returns on April 14. Exclusives from #ETonline : https://www.youtube.com/playlist?list=PLQwITQ__CeH2Y_7g2xeiNDa0vQsROQQgv