Gilder was born in Brampton, Cumbria, England. He is best known for his portrayal of Paddy Maguire on Shameless from 2005 to 2010, and as Styles on Hornblower. He has appeared in Doctor Who (as the Sycorax Leader) as well as New Tricks, Gangs of New York, and the 2004 film, King Arthur. In Mike Bassett: England Manager he was one of the journalists. According to The Sun newspaper, Gilder left Shameless after series 7 with the reason rumoured to be his bad relationship with Actress Tina Malone, who played his character's on screen wife Mimi. He also appears in Poldark as Tholly Tregirls