Writer Tim Foley said: "With Dark Gallifrey, I really got my teeth into Morbius - the way he approached everything, that ego of his that was bubbling out over the script. There was just so much of him that I wanted to write another script to put more of him in. So I asked, please let me write for Morbius again!

"Because Dark Gallifrey: Morbius was inspired by Frankenstein, it felt like a natural fit to put Morbius in another epic story. A large part of Morbius the Mighty is inspired by The Wrath of Khan, which itself has its genesis in Moby Dick. Both are fabulous revenge stories, and basically boil down to a one-on-one. I thought about what Morbius was angry at the War Doctor about, what was driving him, and that's where the drama stems from."

Jonathon Carley said:"Morbius is a legendary character in Doctor Who. So, to throw that character - a big Time Lord tyrant - into the Time War, is a recipe for high-stakes action drama. The history between Morbius and the Doctor is huge, and to go up against him is a big deal - it's a bit intimidating.

"He's from a different time, before the Time Lords stepped back and said, 'OK, we're going to put some rules in here'. And he didn't like it. He was the original rebel. And now he's back at the worst possible time - the Time War - and could destabilise everything. He's got no love for the Daleks, no love for the Time Lords, and he wants to take his rightful place as supreme power in the universe."

Samuel West, the BAFTA-nominated actor who plays Morbius, added: "You can't keep a bad Time Lord down, can you? He has history, you understand how he became who he is, but he's still totally sociopathic, and will calmly and enjoyably pull the wings off flies.

"Morbius has an obsession with the Doctor, and a complex about being unworthy, and what he really needs is a lie down on a nice couch and some care. But he doesn't get that, he gets lots of people telling him he's marvellous. And so his obsessions grow and take him over - the explosions have to be bigger, the conquering needs to be more total, and the victories need to be absolute."

Jonathan Carley at the Soundhouse recording studio

Samuel West

Sheila Ruskin, Theo Solomon and Sam Stafford

Samuel West, Pamela Nomvete and Gareth Armstrong