Doctor Who Season 4 Episode 5
The Poison Sky (2)
The Sontarans continue their evil plot and begin to "choke" the Earth. The Doctor and Donna, now teamed with Martha have to stop them! Can they save Earth before it's too late?
Guest Stars
Billie Piper
Rose Tyler
Freema Agyeman
Martha Jones
Christopher Ryan
Commander Stark
Ryan Sampson
Luke Rattigan
Christian Cooke
Ross Jenkins