Just going to throw this one out there. You know how Moffat tells us that there are connections between Sherlock and Doctor Who we don’t even realize yet? Yes? Okay. So, what if Rupert Graves (Lestrade) for Twelfth Doctor?
Actually never going to happen because Rupert Graves will be appearing in Series 7.
Y’know, alongside the Eleventh Doctor.
Unless they’re pulling some Romana II/Princess Astra nonsense with the whole “I-liked-her-face-so-now-it’s-mine” kind of thing, I really don’t think that this is going to happen.
(And yes, I obviously know about Colin Baker. And no, I don’t think they’re gonna pull something like again. Could they? Well, of course. It’s Doctor Who. Since when has anything ever had to make sense on this show? :P)