Torchwood star John Barrowman says potential ideas to revive the show are being "kept held down" by the BBC.
HBO has also cast 'Poldark' actor Richard McCabe, 'The Crown' star John Heffernan and 'Iron Fist' actor Marquis Rodriguez in the 'Game of Thrones' prequel series.
The next series of Doctor Who is reportedly set for a major scheduling change, after the last series suffered falling ratings.
Matt Smith has defended his choice to play iconic photographer Robert Mapplethorpe in a forthcoming biopic movie.
The BBC is teeing up hours of classic shows for the Christmas period, including archive episodes of Doctor Who and David Attenborough series.