Tom Wlaschiha
From Tardis Wiki, the free Doctor Who reference
Tom Wlaschiha portrayed Koenig in The Sarah Jane Adventures story Lost in Time.
Wlaschiha is a native of Germany, and has appeared in many German and international films and television dramas. In 2011, he appeared opposite Matt Smith as the brother of Christopher Isherwood's German lover in the BBC television film Christopher and His Kind. In 2012, he played the enigmatic assassin Jaqen H'ghar in the HBO series Game of Thrones.