Katy Cavanagh and Matthew Cottle talk about the married couple they play, Grace and George.

What appealed to you about this?

Matthew: It's just a very, very funny script, isn't it?

Katy: Yes, it made me laugh out loud.

Matthew: Yes, really made me laugh. It's just refreshing to get a script that just makes you genuinely laugh.

And how would you describe the tone of it?

Katy: It's definitely an out-and-out comedy. It's traditional but quite quirky as well.

Matthew: Yes, the characters are quite broad but they're very recognisable. So you're throwing a bunch of strangers together in a situation and people are getting bumped off, I mean, it's very funny and very silly.

Katie: And its very ensemble as well, which I think you don't see so much any more.

It's an amazing cast. Have either of you worked with anyone from this cast before?

Matthew: Una Stubbs played my mum in Peter Pan at West Yorkshire playhouse in 1993 or something like that. My kids love Sherlock, so they're quite excited that I'm working with her now.

Can you tell us a bit about your characters?

Katie: Well, we're married. Unhappily.

Matthew: Yes, the spark's gone. And he's become a little bit of a... well, he's got issues. He's got issues but we don't like to talk about them...

How do they fit in with the rest of the characters?

Matthew: Well, we're huge fans of the author David Van Der Clane, which is why we're on the tour in the first place. We're possibly his biggest fans, which is possibly the one thing that unites us.

Katie: That's the only thing we agree on, probably.

What does the 'coach trip' element add to the story?

Katie: It's about being boxed in together. Everybody knows that coach trip thing, don't they? It reminds me of school so much. It's that classic thing of squashing a lot of people in a very small space for a long time and sitting and watching the fireworks happen. So it's very claustrophobic.

Matthew: It's like the Porridge aspect, isn't it? You're thrown together and you can't get out!

Katie: And everyone's being polite... well, up to a point. Grace isn't very polite actually at all. She definitely speaks her mind. And she doesn't really like Mildred and Peggy at all.

Do you know who did it?

Matthew: Oh, yes. We found out at the read through.

Would you have guessed it otherwise?

Katie: I don't think I would have. Oh God, no. I don't think anyone will guess, I really don't.

Matthew: No, no!

What have been standout favourite scenes for you?

Katie: Oh, Blackpool was brilliant! Just being there, and seeing the ballroom. And it was beautiful weather. It was lovely.

Matthew: Yes, and we were on the sea front, they put us up in a hotel and we went out for meals in the evening, it was lovely.

You must get some good gossip in a cast like this. Who has the best gossip?

Katie: Ooh! Una?

Matthew: That will be you, Katy!

Katie: I don't know what you mean...

What is your favourite whodunit?

Matthew: I love Sherlock. The new series, I think is brilliant. It's just one of those things where we will sit down, the four of us, and watch it, the teenagers absolutely love it. It's gone bonkers now. Actually, I completely lose it. It's like Doctor Who, I'm sort of half way through that but I'm not quite sure what's going on. The Christmas special was mad! But it's watchable, so I enjoy that. I used to love the Agatha Christies, I used to watch those when I was a kid.

Katie: I loved Inspector Morse, and Miss Marple. Was it Joan Hickson? I loved that.

Matthew: I did one of those with her.