"I hear from my Irish readers on Facebook that the week of summer in Ireland is officially over now." For a writer whose books feature terrible crimes and very grisly details Karin Slaughter is surprisingly funny, engaging and upbeat on the other end of a phone line - all this at 7.30am. The Georgia-born author has just published her latest thriller, 'Genesis', in which she brings together characters from her Grant County and Atlanta novels. Here she talks about that merger, her plans for the future and the passion of her fans.

Harry Guerin: How did the idea come about to merge the Grant County and Atlanta storylines?
Karin Slaughter:
When I was working on my fourth Grant County book ['Indelible'] I just kind of had this premonition that something really bad needed to happen to change things [laughs]. I'm writing about such a small town with Grant County and you can only kill so many people before everybody moves away. And I thought, 'Y'know I need something to change the series.' Around that time I was starting to work on 'Triptych', which is the first book with Will Trent [the Special Agent in the Atlanta series of books]. And I enjoyed writing about him so much I decided that I wanted to eventually merge these series and have fun and see how these characters and their two worlds collide and how they will blend and not blend.

HG: Was it a difficult thing to do?
Well, y'know, not everybody agreed with my choice, which if you look on Amazon they're very vocal about it - I'm basically a baby killer and I should go to hell [laughs]. It felt really good to make that decision and once I did it was very freeing. And I was able to pull them together relatively easily. I'm not going to just have Grant County all show up in one book with Will Trent in it. So I made it a very gradual thing. We see Sara Linton [central Grant County character] in 'Genesis' and we'll see some more characters show up in the next book.

HG: When you published 'Skin Privilege' in 2007 did you get a lot of flak for killing off Sara's husband, Jeffrey Tolliver?
KS: Yeah [laughs].

HG: Did anyone say 'I think this is a really gutsy thing to do and really great'?
KS: Some people did, but being a very insecure writer - which I'm sure you're very familiar with the breed - I only listen to the bad. I get quite a bit of mail through my website and I would say for every hundred 'Hey you did a great job. I'm so excited about what happens next.', I got one 'You're horrible and I want you to die.' It's those that I concentrated on, of course. I think people have come around now. I'd hope that they've come around now! And I understand that some people feel I've betrayed them and they don't ever want to read another one of my books. Everyone's entitled to their opinion. I would say, thankfully, that not everyone feels that way and they want to see what happens next.

HG: Without giving too much away, at the end of 'Genesis' we see Sara reading a letter. Is that letter going to be a part of the next book?
'Broken' is the title of my next book. It takes place in Grant County and Sara is back home and it's over a Thanksgiving. Hopefully my international readers won't be too puzzled by the Thanksgiving traditions.

HG: Puzzled by the whole concept of it but know when it is.
KS: I was thinking more of Bulgaria than Ireland [laughs]. Anyway, it's the holiday and something really horrible happens.

HG: And has Will ever visited Grant County before?
KS: This will be his first time in Grant County and we see Grant County through his eyes. It's not as lovingly detailed as we get from Sara and Jeffrey and Lina [Adams]. I think people will be surprised that Will sees it as just a little dumpy small town and not this quaint little village that most people think of.

HG: When are you planning on 'Broken' coming out?
KS: Summer next year. I'm halfway through, so that's usually where I need to be. My tour's about to start in the US and that's about three weeks of hell and [then] I'll get back into it.

HG: Was there a temptation at the end of 'Genesis' to have a happier ending?
KS: I'm not one tempted by the happy endings. I think some of my endings are nice. I wouldn't call them happy - the crimes are solved but my characters aren't laughing and sitting around and playing cards. With relationships in my books I'm very careful about them and I didn't want 'Ok, here's Sara and the only other guy in the book is Will so they have to get together.' I didn't think that organically worked. I don't know what's going to happen down the road.

HG: I've been weaned on bad Hollywood movies where everything is resolved.
KS: Me too! But I'm rebelling against it!

HG: On the subject of films, are there are plans to bring your characters to the screen?
KS: Well, we're working on it. It's such a laborious process. As much as publishing isn't run like any business you've ever known, Hollywood is worse. It takes seven years to get a movie done and at any second it can completely crap out. We're talking to television people, I've been meeting with them a lot and we'll see what happens. I want to make sure... And I'm sure as an Irish person you can relate to this, there's a film about Ireland and suddenly there's a leprechaun in it. I'm very sensitive about the South and I don't want them all flaying and talking like Scarlett O'Hara and drinking mint julep and stuff like that. I'm real careful about that. Fortunately the books have done well enough that I don't have to take the money from Hollywood and run.

HG: So would we see them in a film or a TV series?
I'm open to both. But I think like you I was raised on really bad TV and re-runs and I think in a 30-minute storyline most of the time so I would love to see something on television. There are a lot of very strong shows on TV right now - something like 'The Shield' or 'The Closer' with Kyra Sedgwick. There's a lot of opportunity on television.

HG: When you started writing you wrote historical fiction but you couldn't get it published. Would you ever go back to doing it?
KS: I probably would eventually but it would probably be my last or next to last book I write when I'm old and grey because my publishers would just have a heart attack if I decided to do that. 'Why don't you write poetry?!' But it is just an area I'm interested in. The thing is, it would probably be something I wrote alongside the other books. I enjoy writing the other books so it's not like it's a burden to me. But it is something that's close to my heart. I would like to eventually write some sort of historical novel. I would like to write something in every genre eventually.

HG: You're bringing out a book set in the future, 'The Recidivists'.
KS: I'm really interested in the future and especially during the Bush years I had such a sense of an upcoming dystopia. But I think that the elements which were concerning me in that time period still concern me - and that's how we're messing with science. I think it takes great hubris for mankind to think that we can stop global warming if we just do one or two things, that we can totally return our environment to what it was 100 years ago when the fact is that if really wanted to save the environment we'd probably kill ourselves.

And I'm real concerned about drugs that we're using. I don't know how it is over there but here in America every single person is on a cholesterol lowering medication and to me that doesn't seem like a disease, it's seems like a symptom of something else - a symptom of our crappy diet and sedentary lifestyle. And we just take pills for everything. What other strains are we creating with these pills that we're taking? So 'The Recidivists' - it's a good murder mystery and all that stuff - takes place 70 years from now after a pharmaceutical company has caused a horrible plague to wipe out about three quarters of humanity.

HG: Does it still amaze you how passionate readers become about your characters and plotlines?
KS: It's very flattering because I'm wrapped up in this world. I've always been a daydreamer and suddenly you wake up and everyone else is like 'Wow, that's a really good daydream.' It's a validation. I certainly have felt passionate about books, like Emma Donoghue's 'Slammerkin'. Many years ago I bought 10 copies of it and just gave them away because I loved it so much. I understand that passion about books and how when you get a really good one you just want to tell everybody about it. And I feel really lucky that people feel that way about mine.

HG: Going back to when you were writing your first thriller, were you very confident? Was there a censor in your head?
When I write it's just me and it's always been that way. I hope I don't insult anyone when I say I don't write with the thought of my fans in my head. It's always 'This is the kind of book I want to read. This is the story I want to tell.' And of course I'm very pleased once I do it that people want to read it. But in that writing phase there's never really that censor in my head. It's more 'I want to get this story out. 'I want to tell something that's thrilling and gripping.' Because I love reading crime and I love reading thrillers and so when I first started writing in the genre I thought 'I want to write books I want to read.'

HG: I always think there's so much snobbery with books. For me, whatever the style or genre, it all comes down to one thing: do you want to turn the page?
KS: Well, it's funny because a lot of these literary books that everyone celebrates are really genre books. Whether it's 'The Lovely Bones' - that's about a girl that's raped and killed by a paedophile, ok, that's not a crime novel is it? - or even something like 'To Kill a Mockingbird' or 'The Great Gatsby'. Usually when a lot of people who are smart enjoy it they say it "transcends the genre" just because they don't want to think they're reading thrillers but really they are.

'Genesis' is published by Century.