William James Sibree Tudor[2] (born 11 April 1987) is an English actor, known for his role as Olyvar in the HBO series Game of Thrones from 2013 to 2015.

[3][4] He has also appeared in the miniseries The Red Tent,[5] and the Channel 4 series Humans.

[6][7][8] From 2017 to 2018, he portrayed Sebastian Verlac / Jonathan Morgenstern on the Freeform series Shadowhunters.

[9]