19:45Doctor Who (2005–2022)Series 4Episode 5: The Poison SkyBBC One Duration: 45 minutes Audio described Signed Fri 26th Nov 2010, 19:45 on BBC ThreeAvailable for yearsWatch nowAs the Sontarans choke the Earth, the Doctor and UNIT battle to keep both Martha and Donna alive.ContributorsThe Doctor:David TennantDonna Noble:Catherine TateMartha Jones:Freema AgyemanWilfred Mott:Bernard CribbinsSylvia Noble:Jacqueline KingLuke Rattigan:Ryan SampsonColonel Mace:Rupert Holliday-EvansGeneral Staal:Christopher RyanProducer:Susie LiggatProducer:Douglas MackinnonCommander Skorr:Dan StarkeyRoss Jenkins:Christian CookeGenresDramaSciFi & FantasyBrandDoctor Who (2005–2022)SeriesDoctor Who (2005–2022): Series 4 Source: BBC Online