But it’s all a horrible mistake. “Oh Come, All Ye Faithful” is clearly an imposter, a sonic Scrooge in a stringy bit of tinsel and a too-small paper crown – the worst carol of Christmas.

There have been so many Christmas-themed episodes in the history of the series that ... That's right - "O C'mon All Ye Faithful" is the first double-sized episode and it is, of course, built ...