You probably know Sean Bean, who played Lord Eddard of House Stark was also Boromir in the Lord of the Rings. But did you know the scheming Cersei Lannister played King Leonidas's wife Gorgo in 300?
If you are a diehard Game of Thrones fan, you'll no doubt find this gallery full of trivia gems with which to test your friends with.
Believe it or not, several members of the cast previously made appearances in Harry Potter movies. Can you guess which ones?