10 Changes Doctor Who Hoped You Wouldn't Notice
9. Meddling With Time Used To Have More Serious Consequences
Remember the Reapers? Well, that's good, because Doctor Who sure doesn't.
The first series of the 2005 revival firmly established that messing with fixed points in time/creating temporal paradoxes was a big no-no, and if such meddling occurred, bloodthirsty beasts known as Reapers would show up, and murder people willy-nilly.
When Rose saves her father - who, according to established history, died in 1987 - the Reapers materialise and hunt everyone down, attempting to correct the timeline.
But after the episode aired, this entire approach to resolving temporal paradoxes was changed - or, to put it another way, the Reapers were never seen nor heard from again.
Sure, some future NuWho stories would punish time-meddlers in different ways - the collapse of reality in The Wedding Of River Song being a big one - but for the most part, the consequences are trivial, or even nonexistent.
That absolute monster of a paradox created in The Angels Take Manhattan? No Reapers. The Doctor breaking established history in The Waters Of Mars? No Reapers. Hell, even the Doctor saving a family in The Fires Of Pompeii is similar to Rose saving her father, but once again... no Reapers.