VIDEO: Buckingham Palace's Iconic 'Changing of the Guards' Perform GAME OF THRONES Theme Song

During the iconic British changing of the royal guards ceremony at London's Buckingham Palace, home of Queen Elizabeth, the guards surprised the crowd by playing the theme song of HBO's series "Game of Thrones"! Check out the performance below!

The fourth season of HBO's Game of Thrones aired its final episode on Sunday, June 15th. Based on the popular book series "A Song of Ice and Fire," by George R.R. Martin, the hit Emmy-winning fantasy series chronicles an epic struggle for Power in a vast and violent fantasy kingdom.

Members of the ensemble cast include Peter Dinklage, Lena Headey, Emilia Clarke, Nikolaj Coster-Waldau, Kit Harington, Natalie Dormer, Maisie Williams and Sophie Turner. The executive producers are David Benioff, D.B. Weiss, Carolyn Strauss, Frank Doelger and Bernadette Caulfield, and co-executive producers are Guymon Casady, Vince Gerardis and George R.R. Martin.