Kara Tointon and Will Mellor on The Teacher: "There's twists and turns all the way through!"

Kara: "I play Dani, she's an art teacher at a senior school. She grew up in foster care, she's never had a family around her, but she's been in a relationship from her uni days with Emmett [J Scanlan]'s character Tim, who's her husband. I think she's had a really stable, great time until the last few years, when they've lost each other and her marriage has gone a bit stale. But she loves her job and the kids she teaches — if anything, she gives a bit too much to her job, so maybe there's nothing left for her home life and that's why they're struggling. I think you'll feel for her, but you can also see where things are going wrong as well."

Will: "I play Jimmy, who's also a teacher, and he's a father to Matt, who goes to the school. He's split up with his ex-wife, Matt's mother, and I think he's a person who likes to be liked — he likes to show the best side of himself to every person he meets. I think he probably feels quite guilty about what happened with Matt's mother. It's hard to say without giving things away, but there's a lot that's going on beneath the surface with Jimmy."

Kara: "I was sent the scripts, and initially when I read it I was quite shocked by episode one! I suppose for me it was exciting because I've never really played a character who the viewers may initially take a bit of a disliking to, not because of anything in her personality as such but because of the choices she makes quite early on. It was quite shocking for me, but I just kept reading and I thought 'this is definitely something I can get my teeth into' — and working with Will and Emmett was really exciting, as well as Dominic [Leclerc] as a director, so there was a lot going for it!"

Will: "Yeah, more or less the same really — I had seen the first Teacher and, like Kara, I knew I was in good hands with Dominic Leclerc. He'd sort of been mentored by Kay Mellor, and she was one of my favourite directors and writers that I'd worked with. But also, I'm always up for doing things that are a bit different and challenging myself a bit — we've pushed the boat a little bit here and there, and hopefully the audience will come on the ride with us!"

Kara: "I think they've been friends for a long time, and Dani's just so lost, she's got no intimacy or warmth in her relationship any more, and so that moment when her good friend is there for her means so much. She's not looking past that. At that moment, it's really inappropriate, but I guess they can't help themselves!"

Will: "I think Jimmy sees someone who's vulnerable and he's picking up the pieces for a good friend — but at the same time, he's good friends with Tim, so you know, where are Jimmy's morals at? You've got to ask that question."

Kara: "Dani's trying everything she can to save her marriage, but I think she's at a lost end now. Having that ease of talking to someone is the main thing, and then it sort of slips over into a more passionate side."

Will: "It's a tale as old as time, innit? When someone's missing something at home and they get it elsewhere. They end up falling into an embrace and everything else that goes on with that. The sex scene was hanging over us, as any sex scene does, but we wanted it to last longer than it usually would. We wanted to show the passion of it, and at the same time, for it go on slightly longer so that the audience go, 'oh, this is new! We don't usually see this much!' I think that's important because straightaway it puts you on the back foot and shows that we're going to push the boat a little bit more here."

Kara: [laughing] "I think that she's a shockingly bad teacher! There's one line where my character says about the pupils, 'well, they're 15 and 16' — but it's still pretty awful! I think there's no world in which this choice is OK, in any educational system, but this is a drama, so for the purposes of that, you do just get swept up in the clear passion of the moment."

Will: "The problem with Jimmy is that he wants to be everyone's friend as well. He wants to be in there with the kids, 'what goes on tour stays on tour' and all that kind of stuff — he wants to be a teacher but he also wants to be their friend, like he wants Matt to like him as a mate as well as a father. I think it's that grey area you shouldn't cross, and I think Jimmy crosses it a bit too much, especially when they go on the trip. I think he sort of planned it, thinking 'we're away now so you can do a little bit more than you could at school' — so I think he could definitely be a better teacher!"

Will: "I think there are so many layers to this; there's twists and turns all the way through it. Hopefully it's entertaining, but it also keeps you guessing — you always want to catch the audience out! I think it's going to help that it's on for four consecutive nights — we did that for Mr Bates vs The Post Office and it really kept the audience together. There's a lot going on, and you can only put yourself in that situation: can you imagine, as a teacher, being on a school trip where the children are your responsibility, and what happens while mine and Kara's characters are getting up to what we get up to — how do you come back from that? How do you explain that to the parents, and the headteacher, and how do you live with yourself?"

Will: "The strange thing for me is it's set in Stockport, where I'm from, so I thought 'ooh, I'll be going home, I'll be able to see my mum' — and then they said 'yeah, but we're filming in Ireland!' But Lough Dan was stunning — it's right near where they shot Vikings, which really excited me because I loved Vikings. I'd just stand there looking and going, 'that's Floki's house!'. I got to spend some quality time with Kara, which was really nice because I don't know her that well. We were staying in the same hotel, so we'd have conversations and run lines and scenes together, that really helped."

Kara: "When we first turned up in Ireland, we were filming an hour away from where we were staying, and we were like 'why are we being picked up at five in the morning and being driven for an hour, can't we stay nearer?' I think they put us in Dublin thinking we'd want to be in the city, but of course sleep is everything on these jobs when you're in all day every day, so we ended up moving nearer to Lough Dan! I've been so lucky over the last couple of years, Channel 5 and Paramount is a really exciting place to work at the moment. I was in Ireland last year [for Too Good To Be True] and it was incredible, there's a great atmosphere with the Irish crew!"

Kara: "I loved the first season so much — I was planning on watching it over the space of a week because I've got two very young children, and so watching anything is quite tough, but I watched the first episode and I was hooked! I'm a massive fan of Sheridan, and I thought it was fantastic because it made me question my whole belief system. What's interesting is that, being an anthology, ours has no comparison in the storyline as such, it's completely different in its subject, so I hope it's half as good as the first series!"

Will: "Yeah, I think the only similarities are that it's the same director and has had the same eyes over it, and obviously that teachers are involved, but yeah, it's the same title and a completely different story. I hope people tune into this with fresh eyes, not expecting it to be a follow-on from what Sheridan did because it's not, it's a completely new story with a new set of people, and I hope it's as gripping and that people enjoy it as much. That's all you can hope for!"