Everyone thought it was gonna happen - and now it has.
Catherine Tate, aka Donna Noble, has been spotted filming alongside Jacqueline King (Sylvia Noble) and David Tennant. You can see a picture below and Donna certainly looks in fine form!
The most likely theory is that she comes across Verity Newman's book, A Journal of Impossible Things, and her mother and grandfather Wilf (Bernard Cribbins has also been spotted filming) try to stop her from reading it. If she does remember the Doctor, she'll burn up and we can't have that happening to our favourite gobby bride! What do you think of all this?
Thanks to Rob for the tip and SpoilerTV for the picture!