[6] Since appearing in Game of Thrones Ross O'Hennessy has been cast to play the vicious character of Carnage Cliff in the feature film adaption of the comic book Accident Man.

[7] He was accepted into the National Youth Theatre, where he was tutored by actor Hakeem Kae-Kazim and performed in Maggie May, The Tempest and Macbeth in London.

From these plays Ross won a scholarship from Sir John Mills and The Stage newspaper which enabled him to attend a three-year acting course at the Mountview Academy of Theatre Arts.

[13] having played this powerful role in such a big budget production allowed O'Hennessy to move into performances like Rattle Shirt - The Lord of Bones in Game of Thrones.

O'Hennessy is an active supporter of the arts and took part in a charity campaign to save his local theatre[15] where he first started acting at the age of 15.