I got the idea for The Alexander Cipher on a backpacking holiday in Egypt in 1995. My guide-book said the tomb of Alexander the Great had recently been discovered in Siwa Oasis in Egypt’s Western Desert near the Libyan border, so I spent thirteen hours on bus out there only to discover that it wasn’t Alexander’s tomb at all. Never mind. I fell in love with Siwa instead.

During the searing hot afternoons, I’d doze in the makeshift shade of a clothesline on my hotel’s rooftop, pouring ice-water over my forehead, enjoying the panoramic view out over the gorgeous oasis, day-dreaming about desert adventures. And that was the genesis for this novel: a maverick archaeologist on a modern-day quest to find the lost tomb of Alexander the Great.

I wrote a first draft in three weeks after I got home and sent it off to various literary agents in the confident expectation that I’d be the next overnight sensation. Unfortunately, publishing doesn’t work quite that way. It took another twelve years and innumerable rewrites before I sent a sample to Luigi Bonomi, who saw enough in it to ask to invite me in, then to sign me up. He made some terrific specific suggestions about what would make the book more sellable; but most of all, he got me to realise that my job wasn’t to impress readers, but to entertain them.

I rewrote the book once again during the summer, and Luigi sent the revised manuscript out to various publishers on a Monday in September 2006. He warned me it would probably be three weeks or so before I heard anything. After twelve years of rejections, I wasn’t expecting much, if I’m honest. You get inured to failure. When Luigi called late that Wednesday, I was feeling low, I let the answer-phone intercept. But the moment I heard his voice, I knew he had good news. I tripped over a chair in my hurry to get to the phone, almost broke my leg.

Wayne Brookes at Harper Collins had enjoyed the book so much that he’d put in an eye-watering bid. And it didn’t stop there. Within a fortnight, I’d had bids for translation rights from a dozen foreign-language publishers.

An overnight sensation at last— albeit twelve years later!