Hinterland, known as Y Gwyll in the original Welsh language version, is a Welsh language noir police procedural series broadcast on S4C in Welsh from 29 October 2013. The main character, DCI Tom Mathias, is played by Richard Harrington. On 27 November 2013, a second series was announced by S4C. The English-language version, with brief passages of Welsh dialogue, aired on BBC One Wales. When it was shown on the BBC in 2014, it was the first BBC television drama with dialogue in both English and Welsh. A third series of the show began filming in January 2016 and debuted on S4C on 30 October.