10 Best Doctor Who Episodes Written By Russell T Davies

'Turn Left' is the best of Davies 'Doctor-lite' episodes, although that isn't saying a lot when the opposition is 2006's awful 'Love and Monsters'. What is a more worthy sentiment is its ranking as the equal best 'Doctor-lite' episode of all Doctor Who, every bit as good as 2007's 'Blink.'

The episode begins on an alien planet, where the previous actions of Donna Noble are ret-conned for an alien bug's benefit. We are then given the vision of a Doctor-less world, with all the times where the Time Lord saved the day in the last two seasons now not occurring. The scenes exploring this scenario prove to be incredibly powerful, especially scenes showing England coping with the fallout from a nuclear blast on London. The scenes featuring refugees from unsafe cities being moved to 'special camps' is chilling stuff.

The episode also brilliantly incorporates the return of Rose Tyler alongside the growing journey of Donna Noble, with an awkward, and often tense relationship building between the two. The overarching series arch of the 'darkness' approaching and the stars going out are also incorporated seamlessly here, upping the stakes like never before.

The cliffhanger is also a doozy, Tennant using his minimal screen time to maximum potential. But it is in the development of Donna Noble's character where this episode shines. Tate's acting and Davies' writing emphasising just how far the character had come.