Digital Spy caught up with Darvill to chat about his guest role as overbearing barber Bradley Burroughs, the appeal of period drama and his future TV projects...
What can you reveal about your character Bradley in The Paradise?
"Bradley is a barber and he's got a shop next to The Paradise that's been in the family for years and years. I think the shop is getting in the way of The Paradise expanding. They ask if they can buy it off him, but he's a bit of a chancer and thinks he can get a bit more than he deserves.
"He's not the nicest of guys in the world, but he thinks that he is great and he thinks that he deserves to rule the world. He's in his barber shop watching all the ladies go by and he thinks, 'I'm gonna have a bit of that!'"
The BBC has a strong reputation for period dramas. When you hear about something like The Paradise, do you leap at it?
"Absolutely. I heard about it quite a while ago - my agent was talking to me about it. I really wanted to be a part of it because it's just so good. And when I got the call to say, 'Yes, come up and do an episode', I was so excited.
"The set up there is just incredible - they've filled up this whole street and I love stuff like that. I did Little Dorrit a few years ago, I really love doing period dramas. It's stuff like that I really enjoy watching. I've watched the first couple of episodes of The Paradise and I think it's turned out really well - it's something the BBC should be really proud of."
Is there a certain appeal as an actor to doing period drama?
"I think there is, but I don't know quite what it is. I think it's something about that time that was so kind of... the kind of grime and the dirt of it all, and then what I think is so good about The Paradise is, it's got very clean and pristine things in the middle of it.
"The beginning of the department store is something that has just affected us now - the whole process of it all. Independent shops are closing down now so the big ones can take over - over the next 100 years or so, it's got to the point where we go, 'Oh my God, give me a little shop again', so it's something that has got quite interesting.
"There's something about doing a period drama - maybe it's just me overacting the whole episode, but it feels slightly more theatrical! When I saw my costume in The Paradise they gave me a few options of different suits and suddenly there was this suit... it looked like a Mr Toad suit - it was very garish, green and yellow... it's really horrible!
"So I said, 'I'm wearing that one... with a goatee!' - it's just an excuse to dress up and play."
Were you looking for any particular type of role after leaving Doctor Who?
"Just stuff that was different really, and this was really different. It was something that I could really get my teeth into. I just wanted to do as many things as possible. It was really nice to be playing someone who wasn't a nice guy, because I've been playing a really, really nice guy for a very long time!"
So The Paradise was the opportunity do something a bit more heightened?
"I think so. Having done Doctor Who for so long, which has been the most amazing job in the world, and getting into that character so well because Rory was quite close to myself, it was quite nice to create a character that was quite far away from myself."
Your next project is ITV's Broadchurch...
"Yeah, I'm in the middle of filming that one at the moment. I'm off to Bristol during the days, I've been filming some already. It's been going really really well but I'm not allowed to talk about it at all."
Are you allowed to say if you're working directly with David Tennant?
"Yeah, yes I am. He's great. It's just a really, really good script."
The Paradise continues tomorrow night (Tuesday, October 23) at 9pm on BBC One.