Doctor Who: The Timey-Wimiest Episodes Not By Steven Moffat
4. The End Of Time (2009-2010)
When Doctor Who came back in 2005, the entire revived series was built on the mythology of the Last Great Time War, a conflict between the Time Lords and the Daleks which resulted in both races being wiped out (so it was thought) by the Doctor himself.
More than four seasons later, this story brought us inside the events of the Time War for the first time, and showed the doomed Time Lords looking for a way to save themselves.
Their plan involved going back in the personal timeline of the Master to implant a signal in his mind which would plague him all his life, but also act as a tether that would allow the Time Lords to escape the time-locked events of the war after it was over. There, they intended to enact their ultimate plan to win the war by destroying time itself.
The Time Lords were defeated by the combined efforts of the Tenth Doctor and the Master, sending the Time Lords back into the final days of the war to meet their fate.