The Waters of Mars was the third episode of the 2008-2010 specials of the programme Doctor Who. It was totally fucking GOAT (it's not that bloody good, everything was rubbish until Ten went mad.). It starred the Tenth Doctor but had no companions because Tennant was leaving soon and they wanted to save money for Matt Smith's cocaine addiction.
The story is set on fucking Mars (duh) in the year 2059 where the Doctor finds the first human colony is commanded by Captain Adelaide Brooke who is some sort of important character in the history of humanity, so he can't kill her, much as he might want to.
The Doctor must decide whether to use his knowledge of her fate to change history - so of course he flips his shit and declares himself Time Lord Victorious and seizes control of a martian buggy to draw a penis on Mars and calls it the "Penis Victorious." Later the Captain kills herself and that bastion of all that is true about history Wikipedia is altered forever. We see Ten standing in the
rain snow, very sad. Nigga done fucked up. The monster of the week month was a virus that was infecting everyone in the water. Almost as good as "The Happening." Way to see off your money-maker, RTD.
Extremely awesome awesomeness. Arguably Tennant's finest hour. Story-wise it's the logical upshot of the Tenth Doctor's ever-increasing hubris and megalomania. Basically, he may have gone too far in a few places. Pottery.
Everyone on /who/ can relate to the feeling of needing to kill themselves for the better of humanity/the timeline.