The Waters Of Mars (Doctor Who episode)

"The Waters Of Mars" is the second of four Doctor Who specials broadcast in 2009 and the third-last episode to feature David Tennant as The Doctor.

Plot

The episode is based on a space research facility on Mars. The Doctor arrives there in the year 2059 and is brought to the base. However, while he's there, the inhabitants of the base become infected by the water that they come into contact with.

As The Doctor recognizes the base station as a fixed point in time, he begins to wrestle with his conscience as to whether he can get involved.