Markus Zusak's The Book Thief is one of the most cherished novels in recent memory - not simply a monster worldwide bestseller but the kind of tome that readers gush about, recommend to family and friends and re-read time and again.
Inspired by stories told to the 36-year-old Sydney-born author by his emigrant parents, who grew up in Austria and Germany during World War II, The Book Thief is about a family in a small town outside Munich who risk their lives hiding a young Jewish man named Max Vandenburg in their basement.
At the heart of the story is an illiterate girl named Liesel Meminger, whose desire to read and write grows into a powerful oppositional force to Adolf Hitler and his hateful hijacking of the German language, imagination and consciousness during this dark time in European history.
With so much success - the novel spent an astonishing 230 weeks in the New York Times bestseller list - and being such a deeply personal work one would have thought that Zusak would have guarded The Book Thief as greedily as little Liesel does one of the many books she pilfers during the course of the story.
However, Zusak has been amazingly generous in his willingness to let go of The Book Thief, trusting Australian screenwriter Michael Petroni (best known for the second and third Narnia movies) and British director Brian Percival (a veteran of Downton Abbey) to do a first-class job in bringing the novel to the big screen.
"As a fan of both media I never had any qualms about adaptation," said Zusak in a newspaper article he wrote ahead of the film's release earlier this month.
"I've always been able to separate books I love from their movies, no matter how the film turns out. As a reader I've never felt let down or outraged because the film changes things for its own sake. It can never change the book itself. The book will always remain."
Zusak admits he did not put his hand up to adapt the book, which was first published in Australia in 2005, because the writing of it had taken so much out of him.
"It took me such a long time to write that book that it would have been heartbreaking to then have to tear it apart.
"So I was very happy to let someone else follow their own creative course," Zusak tells me over the phone from his home in Sydney.
Despite his open-minded attitude toward the adaptation he does admit that he was disappointed that certain scenes did not make it into the screenplay by Petroni who had the unenviable task of reducing a 500-page plus novel into a couple of hours of screen time.
"After I read one of the early drafts I was disappointed to find two scenes missing - the dream sequence in which Max fights Adolf Hitler in the basement of the Hubermanns' home and the scene in which Rudy blackens his face pretending to be Jesse Owens," recalls Zusak.
The Owens material was reinserted at Zusak's suggestion but the bout between the Jewish streetfighter Max and Hitler was one of many casualties in the always-painful journey from script to screen (along with, unfortunately, the narration by Death, bar a few flourishes at the beginning and end).
"The argument was that as soon as you shoot something like Max's dream you're filming somebody's imagination and you are taken out of the movie. The producers were also concerned about representing Hitler in such an absurd situation. At the end of the day I had to step away and say 'It's your film and you have to make the decisions you think you need to make'."
While Zusak stood away from the production he did make one decisive suggestion to the producer - the casting of French-Canadian actress Sophie Nelisse for the title role of the larcenous Liesel Meminger.
"Normally I wouldn't do anything as bold as that but I had seen her in the superb Canadian film Monsieur Lazhar. I've got a seven-year-old and a three-year-old so my wife and I don't go to the movies much. It was one of the few films we saw at the cinema that year.
"I thought she'd be great and my wife said I should tell the producers. That would never have occurred to me but she insisted and so I did.
"And she ended up in the movie. But I think that will be my one-ever moment of being a casting director," laughs the unfalteringly modest Zusak.
While he has been roped into the publicity machine for this lavish 20th Century Fox production headlined by Geoffrey Rush as Liesel's adoptive housepainter father Hans, he genuinely seems to be happy to be involved with selling the movie, and specially praises the actors.
"They are all wonderful," Zusak says. "Emily Watson as Rosa, Ben Schnetzer as Max, Nico Liersch as Rudy and Sophie as Liesel all fight it out as my favourite but how can I go past the great Geoffrey Rush?
"I can't imagine a better Hans Hubermann."