10 Huge Doctor Who Plot Holes Everyone Overlooks

The Twelfth Doctor episode Heaven Sent is widely regarded as one of the best in the show's history - and with good reason.

Peter Capaldi pulls off a stunning solo performance as the Doctor, who is trapped alone in a mysterious fortress while being pursued by a deadly monster.

In the end, the grey-haired Scot discovers that he is trapped in a loop. Every time he is killed by the creature, the loop resets. He uses this knowledge to punch his way through a diamond wall, taking billions of tiny chunks out of it over billions of years, before finally making his escape.

Not to be a buzzkill or anything, but shouldn't the wall have reset too?

Steven Moffatt, who wrote this episode, has attempted to clear this detail up. He said that the wall isn't part of the castle, it's actually the outside wall of the confession dial, but this reeks of "Oh bother, I better come up with an explanation fast".

Also, we see the castle at the end of the episode, and it isn't anywhere near the edges of the confession dial. So there's that too.