Doctor Who: 10 Best Episodes Of The Last 10 Years
8. The Waters Of Mars (2009)
2009 had a distinct, appalling lack of episodes, but of the handful fans did see, The Waters of Mars was truly revolutionary in terms of the Doctor's characterisation.
This episode was unusual in that it saw the Doctor traveling alone, something rarely seen (usually when one companion leaves, another one joins him almost immediately). During his solo explorations of the universe, the Doctor arrived at Bowie Base One, the first human base on Mars. Coincidentally, he arrived on the same day that history recorded Bowie Base One exploding, killing all of the crew members... and this time the Doctor couldn't save the day. The Bowie Base One explosion was a fixed point in time and so he was forbidden from interfering in the course of that day's events. But as the events leading up to the explosion played out around him, the Doctor decided to break the rules and change the outcome, regardless of what might happen.
The most notable and memorable part of The Waters of Mars was the Doctor's transformation into the Time Lord Victorious, a side fans had never seen before. They knew of his dark side, of course, but to see it come to the fore so abruptly was surprising. It made us feel that the man we had come to now and love was a stranger, and that perhaps we didn't really know him after all.