Steven Moffat: The Doctor returns to Gallifrey like Clint Eastwood – "a mad, bad, dangerous b*stard"

A finale four-and-a-half billion years in the making, Steven Moffat says that "Hell Bent will push the Doctor further than he's ever been pushed before, turning him into a, "mad, bad, dangerous bastard."

 
The final episode continues the story on from Face The Raven and Heaven Sent, the two episodes in which the Doctor lost companion Clara Oswald, was betrayed by immortal frenemy Ashildr and was then teleported to a labyrinthian castle, where he only managed to escape by tunnelling through a wall four hundred times harder than diamond over the course of four-and-a-half billion years. It's a long story. And on the other side of the wall? His home planet of Gallifrey – revealing that it was all a scheme by the Time Lords. 

Speaking to RadioTimes.com, Moffat says, "I think we probably take the Doctor right to the very end of his tether. I've toyed with it in the past but never really gone the whole hog. What would happen if you really, really, really pissed him off? If you took everything from him, broke his heart, kicked the crap out of him and he got up again – what would you be facing then? It's called Hell Bent for a reason. As has been threatened occasionally in the series, what happens when he gets really mad? Well, this is it. Yes, he goes back to Gallifrey, and he goes back in a very bad mood. 
"

"It took a long time to kind of figure out what it'd be like if he went back there. You've seen him go back – I'm going to talk like a tragic fanboy now – in The War Games and he's obviously a bit sheepish; in Deadly Assassin, he's a bit of a bad boy. But now he's the guy who won the Time War. And they'd be terrified if he showed up. He becomes a badass Doctor, and that's always fun as he doesn't do badass very often. He's too nice. But if you push him far enough – and by god, we push him in episode 11 – it all gets a bit Clint Eastwood."