This is my blog. I write about things I like: playing around with continuity and nice cuts. I don't use this blog to point out continuity errors, but rather to celebrate when continuity is used in an interesting way.
Continuity always needs to be right, but sometimes there are deliberate errors. Of course you need a good motivation to do one of these, but I think it's great when it gets pulled of right. One of my favourite ones happens in the fifth series of Doctor Who, in the episode "Flesh and Stone".
In the middle of the episode the Doctor and Amy are in a dark forest (actually the oxygen factory of a ship) surrounded by weeping angels. This is one of Amy's first adventures with the Doctor, she's in a place she doesn't know with a guy she barely knows, so she's scared. On top of that, she needs to keep her eyes closed because she's being infected by a weeping angel. Then the Doctor needs to go away for a while, but right before he goes he comes back to her.
He takes her hand and tells her she needs to start trusting him. It's a really nice showing how their relationship is evolving. It's also a huge continuity error. It's not very visible in the shot, but the Doctor is suddenly wearing his jacket with his sleeves rolled up, he's got a different watch and he's acting a lot more emotional toward Amy.
When this episode first showed it wasn't clear if this error was deliberate or not. It's actually quite difficult to make this error, since he clearly lost his jacket earlier in the episode. The answer came at the end of the fifth series, in the episode "The Big Bang". The Doctor starts travelling back in time and Amy is the only person who seems to notice him. It's important that she remembers him, so he can come back. When he gets to the forest and she's sitting with her eyes closed, he goes to her and the scene plays out exactly like before, with an extra cut to the younger version of the Doctor while they're talking.