Tom Hollander and Olivia Colman talk about the making the third series of Rev...

What's it like being back making Rev?

Tom: Like an old family reunion.

Olivia: Nice, thank you.

What's it like getting back into the characters after almost a two year break?

Tom: I found it very comforting and reassuring and it's very lovely to do something that you have done before which people have enjoyed. There was none of the stress you normally have playing a new part where you go, 'Oh, I wonder if it works if I do this or if I do that'. Because we've done two series, there's a relaxation of putting on a favourite old cardigan or something.

Olivia: A subsequent series is always more fun for me. There's something comforting about knowing we're back because people liked it, so we're doing something right. It's a shame you have to do anything on the first day. It'd be nice if it was a write-off because you're just chatting and catching up. It's lovely.

Why such a long wait between Series 2 and Series 3?

Tom: We'd been doing Rev for about two years non-stop with writing, researching and post-production. It takes a long time to create the show. It takes us much longer than you would think.

Olivia: Yes, people don't know how long it takes to research and write. It takes a good year to write, doesn't it?

Tom: It seems to take us that long. Each series took us about a year, between drafts and all the research, a good year. We're very slow.

What does the research entail?

Tom: That involves talking to vicars. For the first two series we spoke with a lot of vicars, finding out about their lives, what sort of things happen to them and from those we would get our plots. In this series we wanted to find one big story that would take us all the way through the series and, having thought of the story that we wanted to tell, we then had to go and talk to vicars about making it plausible, checking it was the right sort of thing. This series we're telling a story in which the vicar gets into trouble and encounters something called 'conduct unbecoming' and we had to find out what that was and how it worked.

What do viewers have in store for Series 3?

Olivia: A baby.

Tom: Yes, there's a new baby which messes up their lives more, screws up their sex life and invites more people into their house.

Olivia: The baby belongs to the Parish suddenly. So, everyone who is knocking on the door anyway is now also knocking on the door to look after the baby.

Tom: Everybody wants to be a godparent.

Olivia: ... which is very irritating to Alex.

Tom: There are new bosses in the church who are bearing down on Adam who is, as ever, struggling to pay for his huge draughty, leaky building. The tensions between Alex and Adam are still there and the tension between Adam and the Archdeacon are still there.

All the same elements that we saw in Series 1 and 2 are still there but they just get pushed to an extreme level.

There are some great guest stars. What do they bring to this series?

Tom: They all bring a certain amount of brilliance. Kayvan Novak brings glamour and handsomeness. Joanna Scanlan and Vicki Pepperdine are an utterly brilliant double act; they bring pressure on to the Archdeacon because they are above him in the church hierarchy.

Olivia: The Archdeacon doesn't play low status very well. There is lots of comedy from that.

Tom: You almost feel sorry for the Archdeacon at times. Kayvan is a very glamorous figure relative to Adam because he is an Imam with a congregation of a thousand people who gets high-fived when he walks down the pavement by his congregation, which is a very different world from the one Adam inhabits.

Do you think having a child has changed Adam and Alex in the series?

Tom: They're still not having sex.

Olivia: It's always been a cause of concern hasn't it? That they're not home enough or want, whichever. But that's even more so now, because even if they did have a moment to have sex they're too knackered.

Tom: Also, crucially, Alex has been promoted in this series. Alex has a new and important job so she's under a certain amount of stress at work, as well as the child, so she is also under pressure. So Adam and Alex see less of each other and that's put a strain on things.

Tom, you've written your first episode this series. What was it like?

Tom: It was thrilling. Though, I found it embarrassing when we were shooting it because the lines that we had to say didn't feel like lines at all. Normally when you're learning something you're grappling with someone else's brain, because they wrote them, whereas when it's your own it just feels like chat. It's now put together and I'm really glad about it and it works really well as an episode so I feel proud of it.

I've always storylined the episodes with James and written scenes etc along the way, but actually stepping up and sticking my head above the parapet and doing a whole one on my own was a wonderful thing. It was also good because it meant that the third series had a new challenge in it for me - a very happy thing.

Were you surprised by the massive reaction to the show?

Olivia: No, you get kind of a gut feeling when you first read a script. I really liked it. I don't think I have particularly unusual taste, I think I have a very average litmus test. So the fact that other people really liked it too then, yay! It's because it's well written, it's beautiful and the people are loveable and flawed. It's got a soft underbelly; it's got a humility which is easy to love, when something is terribly arrogant it's also impossible to love it. So I think it makes sense that people have loved it.

What's your favourite episode to date of the series?

Olivia: I loved the Christmas episode from Series 2. I remember the breakdown at the front of the church and just finding it incredibly moving and feeling awful that you're finding it funny. I loved it.

Tom: My favourite is the final episode from Series 1, the 'You f**k off', 'No, you f**k off' episode. The one with the vicar and tarts party.

Olivia: Oh, and you dancing! Again.

Tom: Not so much the dancing but yeah, our row. You dressed up as vicar walking down the street. Olivia wearing a moustache.

Olivia: I quite liked being dressed up as a vicar.

Tom: That was fun.

Olivia: That was fun actually. Good one, I like that one too.

Series 3 of Rev is on BBC Two on Monday nights at 10pm.