Question:  who is one of the actors of the show that Mathew Horne appeared on 
Context: Roman's Empire was a British television comedy show starring Mathew Horne, Neil Dudgeon, Chris O'Dowd, Montserrat Lombard and Sarah Solemani.  Written by brothers Harry and Jack Williams (sons of writer Nigel Williams) as their TV writing debut, the programme's first episode was shown on BBC Two on 12 April 2007. The first series of British television sketch comedy "The Catherine Tate Show" premiered on BBC Two on 16 February 2004.  It consists of six episodes and concluded on 22 March 2004.  In the first series audiences are introduced to various characters portrayed by Catherine Tate, including Joannie 'Nan' Taylor, Lauren Cooper and Bernie, the Irish nurse.  The series was entirely written by Tate alongside Mathew Horne, Derren Litten, Aschlin Ditta, Arthur Mathews and Bruce Mackinnon. Gavin & Stacey is a British sitcom that follows the long-distance relationship of Gavin Shipman (Mathew Horne) from Billericay in Essex, England, and Stacey West (Joanna Page) from Barry in the Vale of Glamorgan, Wales.  The writers of the show, actors James Corden and Ruth Jones, also co-star as Gavin and Stacey's friends, Smithy and Nessa.  Other prominent cast members include Alison Steadman and Larry Lamb, who play Gavin's parents, Pam and Mick, and Melanie Walters and Rob Brydon, who portray Stacey's mother, Gwen, and her uncle, Bryn. Vera Filatova (born 6 November 1982), also known as Vera Graziadei, is a Ukrainian British actress.  She is best known for playing "Elena" in Channel 4's cult series "Peep Show" alongside David Mitchell and Robert Webb.  She also played "Eva" in "Lesbian Vampire Killers" with James Corden and Mathew Horne; and "Svetlana" in a five-part BBC1 drama "The Deep" opposite Minnie Driver, James Nesbitt and Goran Višnjić. The following characters appear in the comedy sketch series The Catherine Tate Show on BBC Two.  Comedian Catherine Tate portrays all of the characters featured most prominently in the show, which she created with Derren Litten and her team of writers.  Other actors who have supporting roles throughout the series include Mathew Horne and Niky Wardley. "Gavin & Stacey" is a British romantic situation comedy that follows the long-distance relationship of Gavin (Mathew Horne) from Billericay in Essex, England, and Stacy (Joanna Page) from Barry in the Vale of Glamorgan, Wales.  The writers of the show, actors James Corden and Ruth Jones, also co-star as Gavin and Stacey's friends, Smithy and Nessa.  Other prominent cast members include Alison Steadman and Larry Lamb, who play Gavin's parents, Pam and Mick, and Melanie Walters and Rob Brydon, who portray Stacey's mother, Gwen, and her uncle, Bryn. Mathew Frazer Horne (born 6 September 1978) is an English actor, comedian, television presenter, and narrator.  He is best known for appearing on several BBC sketch shows and sitcoms, most notably "Gavin & Stacey" (as Gavin Shipman), "The Catherine Tate Show", "20 Things to do Before You're 30", "Teachers", "Horne and Corden", and "Bad Education". Horne & Corden is a British sketch show written by Jon Brown, Steve Dawson, Andrew Dawson, Tim Inman and the cast, script edited by Sam Ward, and starring Mathew Horne and James Corden.  It aired on BBC television in 2009.  The first episode was broadcast on 10 March 2009 on BBC Three.  It is presented by and stars Mathew Horne and James Corden in front of a live audience, featuring pre-recorded sketches (often on location) and vignettes filmed in a studio with an audience.  Several episodes featured a song and dance routine as their finale.  The first episode attracted the highest ratings for a comedy show debut on BBC Three.  However, ratings quickly dropped throughout the show's run. "Horne & Corden" is a British sketch show written by, and starring, Mathew Horne and James Corden (Gavin and Stacey) and aired on BBC television.  The first episode was broadcast on 10 March 2009 on BBC Three.  It is presented by Mathew Horne and James Corden in front of a live audience, in a style reminiscent of "Morecambe and Wise", featuring pre-recorded sketches (often on location) and vignettes filmed in a studio with an audience.  The first episode even had a song and dance routine as the final piece of the episode, still in keeping with a "Morecambe and Wise" tradition of variety/comedy show.  The first episode attracted the highest ratings for a comedy show debut on BBC Three. "Gavin & Stacey" is an award winning British television comedy series, following the lives of the title characters Gavin (Mathew Horne) and Stacey (Joanna Page), who, before marrying, live on opposite sides of the country, Gavin in Billericay, Essex, and Stacey in Barry Town, Vale of Glamorgan.  During the first two series Gavin lives with his parents Mick (Larry Lamb) and Pam (Alison Steadman) but in the third series he has moved, with Stacey, to Barry and lives with Stacey's mum.  He has a best friend Neil "Smithy" Smith (James Corden).  For most of the episodes Stacey lives in Barry with her mum Gwen (Melanie Walters), with an extended family of Uncle Bryn (Rob Brydon) across the street, and best friend Vanessa Shanessa "Nessa" Jenkins (Ruth Jones), but for a short while during series two she lived with Gavin, Pam and Mick in Essex.
Answer: Ruth Jones