10 Most Unexpected Doctor Who Moments

Death is perhaps the only certainty in Doctor Who. Every incarnation of The Doctor must meet their end at some point, and when that is exactly, usually becomes very apparent when the actor announces they're leaving.

But back in 2008, David Tennant was at the height of his popularity, so the idea of him regenerating was unthinkable. Which is what made the The Stolen Earth's cliffhanger so good.

Series 4 had teased us with the return of Rose Tyler and every fan's dream seemed to be coming true when Ten and Rose were finally reunited in the penultimate episode. But just as they approached each other, a Dalek appears, fires his weapon and The Doctor is killed.

As Tennant begins to regenerate, the credits roll on one of most unexpected finales to an episode ever, which left audiences everywhere speculating whether Tennant was leaving and who his replacement would be.

Of course the answer would be that the Doctor technically regenerated but kept Tennant's appearance. But nevertheless, few Who moments have garnered more widespread interest than this one.