10 Most Chilling Doctor Who Moments

Perhaps setting up the central premise of Torchwood: Children of Earth a year later, Turn Left depicts just how horrendous the UK government can be towards its population when the Doctor isn't around to take a stand.

In the wake of the nuclear devastation wrought by a full-size replica of the Titanic, Donna and her family are forced to relocate to Leeds. In the face of adversity, they begin to bond with the Colasanto family, one of many families they have to share their over-crowded home with.

So it's utterly devastating – and a chilling moment that continues to become more resonant as the years tick by – when the Colasanto family is sent to a "labour camp". The concept of a beleaguered UK government sending immigrant families to work in camps is bleak enough as it is, until Wilf reminds us that "labour camps" is "what they called them last time."

Of course, Wilf is referring to the Holocaust, and the concentration camps used by the Nazis to commit genocide against Europe's Jewish population. It's a single line, delivered beautifully by Bernard Cribbins, that absolutely breaks your heart, as it forces us to consider how our real-world UK government would handle such a desperate situation.

Russell T Davies has always excelled at weaving these societal and political nightmares into Doctor Who, as seen recently in Dot and Bubble. But he's yet to top the feeling of hopelessness conjured up by Turn Left's bleak alternate reality.