19/09/2016 7:25 AM AEST | Updated 19/09/2016 7:27 AM AEST

'The Rosie Project' Author Has A Brand New Book

It's called 'The Best of Adam Sharp' and we're pretty excited.

Melbourne author Graeme Simsion.

If you're one of the millions of people around the world who fell in love with The Rosie Project (and are frustrated with how friggin' long it's taking to make it into a movie, already), we have good news for you.

While the movie version is still in development (both Jennifer Lawrence and Richard Linklater dropped out from the project last year), the Aussie author who brought us both The Rosie Project and its sequel, The Rosie Effect, now has a new book for you to sink your teeth into.

Titled The Best of Adam Sharp, Graeme Simsion's latest offering ventures past the world of Rosie and Don and into new storytelling territory, this time focusing on a 50-year-old IT contractor and music trivia whiz Adam Sharp, whose world is turned upside down when an unexpected email suddenly presents him with the opportunity to rekindle a romance from 22 years prior.

"It's a story about a love affair rekindled," Simsion told The Huffington Post Australia. "It's about the girl he left behind -- the great love of his life -- who gets back in touch 22 years later.

"She is on the other side of the world -- he lives in Manchester, she lives in Melbourne -- and is basically 'the one who got away', the great love.

If you had the choice between what I call 'companion love'... versus something that would suddenly put passion back in your life, what would you choose?

"Except Adam is in a long-term relationship, he has been involved with a woman for 20-odd years. So this sudden communication throws up a bunch of moral and emotional questions.

"If you had the choice between what I call 'companion love' -- so that kind of long-term, committed love, where you're good buddies and you put out the garbage every week and so on, but there's not that much passion -- versus something that would suddenly put passion back in your life, what would you choose?"

Mario Anzuoni / Reuters
Jennifer Lawrence was attached to star in a movie adaptation of 'The Rosie Project' but then pulled out due to 'scheduling conflicts'.

Simsion's inspiration for the story actually arose from a real-life situation, when his wife was contacted by an old flame who was going through a divorce.

"My wife's ex-boyfriend sent her an email and said, 'I'm pretty devastated, I just broke up with my wife'," Simsion recalled. "We were holidaying in France at the time and she asked me if she could invite him to stay a few days. They had kept in touch, so it wasn't totally out of the blue.

"I said 'no way', but I was left with this guilt, you know, what if he topped himself or something? It would be down to me. So I said, 'Fine, three days maximum'. He ended up staying for five or so, and it was fine, we all got along. But it did get me thinking, 'What if things had been different? What if he was the great love of her life?'"

Given The Rosie Project was Simsion's debut novel, not to mention such a huge success (the rights were sold in over 40 countries), it would be understandable if the author was feeling a bit jittery about releasing his first non-Rosie-related work.

"Actually, I'm fine about it," Simsion told HuffPost Australia. "Financially I'm okay. I don't need for it to be a bestseller. But so far, I've had really good feedback from the people who really count, and they seem to have all jumped on Adam Sharp. One existing publisher decided not to, but we had another publisher on board, offering the same money, almost straight away, so it wasn't a problem."

I just try to make my characters real people, who make good decisions and bad decisions, but always well-intentioned decisions.

But Simsion does have some words of warning for The Rosie Project fans -- Adam Sharp is no Don Tillman.

"Adam is someone we've probably met before, whereas Don was a bit more eccentric," Simsion said.

"I didn't think women would fall in love with [Adam], but just last night I was talking to a woman I know in her late 40s, and she said she read that last chapter over and over again, and if she ever met a guy like Adam, that would be it for her.

"Sometimes I don't know what I'm writing or how people will respond. I think I just try to make my characters real people, who make good decisions and bad decisions, but always well-intentioned decisions.

"People relate to that sort of thing, to humans just being human."

Hannibal Hanschke / Reuters
Ryan Reynolds is reportedly in talks to play Don Tillman in the film adaptation of 'The Rosie Project'.

While The Best of Adam Sharp will be available in bookstores and to download on e-readers as of Monday, 19 September, those who prefer to listen to words rather than read them can also grab a copy of the audio book via Audible.

"I think it's very challenging when you do these things, how much you choose [someone] to do the character and how much you just read the words on the page," Simsion said of casting a narrator for the audio version.

"The book is written like a first person monologue. This is a guy telling us how it went down. I guess, when I was choosing [the narrator for Adam Sharp], I was looking for someone where I could say, 'yep, I could sit around and listen to this guy tell this story'.

"We also needed a guy with a Northern British accent. It was important he was from Manchester. Really quickly, Audible came back to me with eight or nine auditions, and I have to say, every one of them was acceptable. I would have been happy with a book done by any of them.

"But I sat down with my wife, who thinks Northern England accents are sexy, and said 'Alright let's rate them out of 10 and see how we go'. Turns out, we rated them virtually identically. And we were absolutely clear on what the best one was, there was no doubt about it."

It's not an ending where everyone lives happily ever after with no downside. It's more realistic.

As for what fans can expect from The Best of Adam Sharp, Simsion has this to say:

"What it isn't is a standard romance or rom-com. A complaint I got from one of my editors was that, when Adam chooses between long-term love and the one who has sparkled up from the past, it's not an ending where there is a happily-ever-after, unconditionally.

"Because normally, you'd have a situation where he discovers this girl he has been living with has actually been super romantic all along, and they become really passionate and therefore he gets everything.

"In this story, he has to make a choice, and with either option, you have to lose something. It's not an ending where everyone lives happily ever after with no downside. It's more realistic. It's more like real life."

'The Best of Adam Sharp' hits stores on September 19, 2016.

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