Minor spoilers ahead! 

If Turn Left once again demonstrated Doctor Who’s ability to pull the rug a little, then we can’t say that the clues weren’t there, waiting to be seen. Granted, they weren’t easy to see, but here’s what we know for definite, as well as some questions that still need answering...:

* Right throughout the series, there’s been mention of disappearing bees. We’ve counted this a few times, and while there’s been no explanation as to why – and it still could be a red herring, of course – it was there again in Turn Left. What’s going on there, then?

* There's also been more obvious mention of disappearing planets, and true to form, the stars have begun to pop out of the sky, as we're promised the darkness is coming. The title of the next episode, The Stolen Earth, also ties into this.

* More obvious was the formal return of Billie Piper as Rose Tyler, whose face has popped up several times throughout the series. In fact, she was last seen screaming the Doctor’s name on the background screen in Midnight, and appeared even in the first episode of the series.

* Now it’s get interesting. We can’t track down a specific example, but do we remember someone making mention of something on Donna’s back earlier in the series? Does that mean that, in spite of being on a parallel timeline in Turn Left, the strange creature was actually with her throughout the series? Was she therefore, being diverted onto this timeline that we’ve been seeing these past weeks all along? That would make sense of the Doctor’s comment that how coincidental it is that he should meet Donna Noble twice. Or have we gone mad?

* Finally, and hats off to Den Of Geek contributor Gaye Birch for this, how about the picture that was set in the background of Doctor Moon’s office in Silence In The Library? Is that a child’s drawing of Rose Tyler and a wolf? It sure looks like it to us....

Share your speculation down in the comments field…!