Popsugar Entertainment Game Of Thrones Game of Thrones Prequel Cast It's Really Happening, People: Here's Everyone Joining the Game of Thrones Prequel Cast 1 November 2018 by Quinn Keaney First Published: 31 October 2018 View On One Page Photo 12 of 15 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 12 John Heffernan Heffernan has a vast list of theatre credits, including appearances in The Crown and Collateral. Previous Next Start Slideshow Game Of ThronesEntertainment NewsNaomi WattsTV