Last month, Zack Snyder's Sucker Punch got – for want of a better way of putting it – sucker punched. Expected to bow at the top of the US movie charts, this noisy CGI effort was beaten to the coveted No 1 spot by a cheeky upstart, Diary of a Wimpy Kid: Rodrick Rules.
The second film inspired by the bestselling book series by Jeff Kinney, it's little wonder that the 40-year-old author has such a smile on his face. "For it to go up against a special-effects juggernaut and to come out on top was enormously satisfying," he says.
If all this doesn't mean much to you, you probably don't have young children. But Kinney is right up there with J K Rowling as one of the bestselling children's authors on the planet. In the US alone, 50 million Wimpy Kid books have been printed, while American books giant Barnes & Noble recently listed Kinney's works as the most popular series for children aged 9 to 12, above even Harry Potter. Kinney's series has been translated into 33 languages, and close to 9 million copies have been sold in the UK. Last November, when the latest instalment, Diary of a Wimpy Kid: The Ugly Truth, was published, it was selling at a rate of one copy every 11 seconds.
So revered has he become, Time magazine even named Kinney one of the 100 Most Influential people of 2009. "I actually thought that was a practical joke," he tells me. "In fact, I did a lot of work towards trying to track down the source of the joke. I was very surprised to find out that was a real thing. But I'm on the bottom right-hand corner of the cover, so I'm probably at great risk of falling off!" Modesty aside, it shows that Kinney – who only published the first of his five Wimpy Kid books in 2007 – can't quite believe what's happened to him over the past four years.
It's an understandable reaction from a cartoonist who started his career inking strips for the University of Maryland student paper. But the truth is that the Wimpy Kid books have become a full-blown phenomenon. At their core is a likeable hero – the pre-pubescent Greg Heffley – whose epistolary accounts make him teen literature's most beguiling diarist since Adrian Mole. With each book filled with hand-written notes and cartoon illustrations of his day-to-day activities, as Kinney puts it, they look "very inviting to a kid pulling them off the shelves."
Yet there's more to the books than simply being an appealing read. While Kinney hits on the books' mischievous humour – "they're entertainment for entertainment's sake" – he also doesn't patronise his readers. "I don't write down to kids or teach them lessons, other than possibly that reading can be fun," he adds. In Greg Heffley, he's created a hero whose growing pains are entirely relatable. "The average kid knows what it's like to feel powerless in the world, and I think that Greg is very self-aware and self-conscious. With that comes the awareness that he doesn't have much of a say about how life is going to go."
Remarkably, the film adaptations have managed to maintain Kinney's irreverent tone. Starring Zach Gordon as Greg, the first, Diary of a Wimpy Kid, globally took $75m last summer, with a further $30m in DVD sales. If that indicates that Kinney's loyal fanbase were willing to put their books down and head to the cinemas, partly this can be attributed to the fact that Kinney's own cartoon drawings have been slavishly recreated, animated and spliced in with the film's live-action scenes. "It meant I got to see my characters in motion for the first time," he says, "which was cool."
Even more so than J K Rowling on her Harry Potter series, Kinney has been a driving force behind the film adaptations. Credited as executive producer on both films, "I think I was as involved as an author can be, or can reasonably hope to be," he says. "I was there from the very first days, of putting together the treatment. I worked with the screenwriters quite a bit. Contributed jokes and scenes for the movie. I was there on set for about half the filming, helped with the casting, gave my input on the principal actors. And then I worked through post-production on the animations, with the animators."
In this second movie, directed by David Bowers, Greg must contend with his older brother, Rodrick (Devon Bostick), whose only preferred past-time to bullying his sibling is playing in his rock band, the amusingly named Löded Diper. What's more, Greg is still trying to survive the trauma that is middle school – an ordeal based on Kinney's own "scary" experiences of this particularly tricky pre-pubescent pit stop. "It felt like we were being segregated from the general population," he says. So what was he like at school? "I was a little bit invisible, I guess you could say. I felt like I was observing the scene and not really acting in it. From the teacher's point of view, I was probably more or less forgettable."
The Fort Washington-raised son of a military analyst who worked at the Pentagon and a mother who ran a pre-school, Kinney has certainly taken the long way round to success. After graduating with a degree in criminal justice, he ended up working as a layout designer for a small Massachusetts newspaper and later a software engineer. He started writing the Wimpy Kid journals – originally intended as a nostalgic read for adults – and eventually persuaded the games website where he was working to publish them. While that gained him a loyal online following, it was only in 2006, when he attended the New York Comic-Con, that he met a publisher willing to put them in print.
Judging by the letters he now gets from delighted parents, amazed at their children's new-found love for reading, reshaping them for a younger market was the right move. Still, you get the sense that Kinney feels a little uncertain. Is he an author or a cartoonist? "It's really a strange thing," he sighs. "For example, I'm going to speak at the National Cartoonists Society in a few weeks and I don't feel like I'm a part of that group because I never could legitimately break into that profession. Then, on the other hand, I sometimes go to author conventions and I don't feel like a real writer or novelist. So I think I'm caught in this hazy middle."
Even his children seem to be a little critical. A father of two boys (Will, 8, and Grant, 5 – from his second marriage, to Julie), he recently found that his eldest went from the first Wimpy Kid book to the third, missing out on the second. "Because, as he said, I don't do such a good job of carrying on the plot like Harry Potter!" It's certainly stopped him seeing himself as the new J K Rowling. "I think that J K Rowling is in a completely different category," he says. "Her phenomenon was probably a once-in-a-lifetime, once-in-a-generation phenomenon. I'm a successful author for kids. But she's in a different category because of the quality of her writing. I'm a joke-writer. She's a storyteller. And there's a world of difference in between."
Perhaps the main difference is that, rather remarkably, Kinney still has a day-job, working for the Family Education Network, the Boston-based company behind the online game Poptropica. A "virtual world for kids", as Kinney puts it, with about 10 million unique visitors a month, it's styled as a series of islands – each one with a quest to complete – that users can visit with their own digitally rendered character. Recently, Kinney added a new island, "Wimpy Wonderland", allowing users to explore the Wimpy Kid universe using their avatar. An educational tool that markets his books to children, it would feel a little insidious if the Wimpy world wasn't so loveable.
As for his own children, Kinney seems rather strict. Take the issue of violent video games. "I'm actually not a fan," he says, sounding like the tut-tutting father of Greg's friend Rowley in the Wimpy Kid books. "I favour the Mario Nintendo games. We don't actually have any violent video games in our home, and I hope we don't have to go there eventually." The way Kinney paints it, his household is a rather wholesome one. "My kids like to sit in my office with me and watch me draw. So they get to see the books come to life long before they hit the shelves."
Currently working on a sixth Wimpy Kid book, which is due at the end of the year and promises to see Greg's family snowed in in their home, Kinney admits it's getting tougher to come up with fresh ideas. "It's hard to figure out what parts of childhood I haven't yet explored, and how to keep things fresh," he says. As for the movies, he wants to see at least two more of his books adapted before, like Greg, his fast-growing actors hit those awkward teenage years. With the last Harry Potter film due this summer, there is obviously a gap still to fill. "I feel like we created a good thing in the world," he says, "and I'm proud of that."
'Diary of a Wimpy Kid: Rodrick Rules' is in cinemas now