10 Most Terrifying Deaths In Modern Doctor Who
3. Don't Drink The Water
Arriving on Mars' Bowie Base One during the events of 2009's The Waters of Mars, the Tenth Doctor saw an alien virus infect the human colonists - possessing them and controlling the water in their bodies.
Unable to save the colonists due to the event being a fixed point in time, the Doctor was forced to watch them die one by one. First infected by the alien Flood was Andy Stone, whose eyes became whited-out and the skin around his mouth cracked and blackened. Infecting more of the crew, the Flood planned to invade the Earth next.
Drenching the humans in infected water, the Flood almost completely took over the Base before the Doctor and Adelaide Brooke were forced to detonate a nuclear device. The possessed humans were killed instantly, but the Doctor managed to return Adelaide and some survivors to Earth in the TARDIS.
Realising that her death was meant to be a fixed point in time, and the Doctor had gone too far, Adelaide decided to take her own life. This made for a particularly harrowing moment in an episode haunted by iconic Doctor Who horror.