Silent Witness is a British crime drama television series produced by the BBC, which focuses on a team of forensic pathology experts and their investigations into various crimes. First broadcast in 1996, the series was created by Nigel McCrery, a former murder squad detective based in Nottingham. (He later went on to create the series New Tricks, with writer Roy Mitchell.) Twenty-three series of Silent Witness have been broadcast since 1996. Amanda Burton starred as primary character Dr. Sam Ryan before leaving the show during the eighth series. Since her departure the series has featured an ensemble cast, which consisted of Emilia Fox, David Caves, Liz Carr and Richard Lintern until the end of series 23, when Carr and Lintern both departed. The programme is broadcast in more than 235 territories, including ABC in Australia, Showcase and the Knowledge Network in Canada, KRO in the Netherlands, TV One and Prime in New Zealand, BBC First in South Africa and BBC America in the United States. Silent Witness continues to achieve good audience ratings in the UK. In 2011, for example, Series 14 attracted an average audience of nine million viewers.