Sir Geraint in the episode The Curse of Cornelius Sigan of the BBC drama series, Merlin. His character, Sir Geraint was introduced as Arthur's second-in-command. He's a figure from Arthurian Legend, is given a prominent speaking-part, and had several promotional shots taken of him. He's never seen again, and his role is taken over by Sir Leon, who makes his first appearance in the next episode. Whether his one-off appearance was intentional or not is unknown.
Neal also performed for the Royal Shakespeare Company in Stratford Upon-Avon, London and the USA. He has played a role in the TV Series Doctors (2011), Spooks (2011), Scott & Bailey (2011), and Doc Martin (2009), to list a few.