One mysterious employee of Transport for London has a serious passion for Doctor Who.

The above homage to the Time Lord, a quote from programme writer Steven Moffat, was left at Tufnell Park Tube station this morning (or was it from the future) in anticipation for the start of the new series later this month.

But it's not the first such message to be left on the London Underground - last November, the below message was left at Tufnell Park and then again in January...