HBOsGame of Thronesprequel has added a second actor to its cast.

British actor Josh Whitehouse has gotten on board the pilot.

Hes best known for his role in the Masterpiece seriesPoldark.

Armand de Brignac Art World Dinner, London, UK - 02 Oct 2018

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The news comes the day after EW reported thatNaomi Watts was joining the seriesin a starring role.

Also inGoTprequel news, author George R.R.

Martin wrote on his blog that the shows title is indeedThe Long Night.

HBO hasnt confirmed this, however.

No word on what character Whitehouse will play.

Watts is playing a character described as a charismatic socialite hiding a dark secret.

The prequel project will still need to be ordered to series to make it on the air.

If it does, the soonest it will premiere is 2020.

Meanwhile, the final season ofGoTairs in the first half of 2019.