He has a new one out with a new angle on the Roaring Twenties -- rum running instead the of the usual whiskey smuggling. And, I can just see the film, as he describes in an NPR interview how he found his way to Live By Night. And, most readers can, too, which is why his are the book-to-film novels of choice.
Readers of this blog post might say, "Wait a minute. What about Ian Fleming's James Bond? Yes, yes, there is the 007 Franchise. My comment about Lehane's percentage is not my own, but "heard" (probably from that dastardly National Public Radio -- a socialist name if anyone's ever heard one). I think there have been more films made of James Bond than any other fictional character, although Miss Marple and Inspector Clouseau might be in the running, also. However, Agatha Christie's character has not transcended the ages as Fleming's has (the first James Bond novel, Casino Royale was written in 1953), and Inspector Clouseau was a Blake Edwards/Peter Sellers invention directly to the screen, not from a novel. Casino Royale introduced James Bond, but the first film made introducing James Bond was Dr No with the unforgettable scene of Ursula Andress rising from the sea like Venus from foam. However, it still used the characteristics of Bond with which Fleming endowed him, including the famous drink, although not entirely the correct recipe, as done in the Casino Royale:
'A dry martini,' he said. 'One. In a deep champagne goblet.'You see, it's not merely a martini, shaken, not stirred. It's an entirely different drink and Bond ultimately called it the Vesper.
'Just a moment. Three measures of Gordon's, one of vodka, half a measure of Kina Lillet. Shake it very well until it's ice-cold, then add a large thin slice of lemon peel. Got it?'
'Certainly monsieur.' The barman seemed pleased with the idea.
'Gosh, that's certainly a drink,' said Leiter.
Bond laughed. 'When I'm ... er ... concentrating,' he explained, 'I never have more than one drink before dinner. But I do like that one to be large and very strong and very cold, and very well-made. I hate small portions of anything, particularly when they taste bad. This drink's my own invention. I'm going to patent it when I think of a good name.'
— Casino Royale, Chapter 7: Rouge et Noir [as copied out of Wikipedia entry -- but read the book; you'll see!]
What is really great is that Casino Royale, which has been out-of-print for 10 years, is now back in print, mainly due to a new Bond film (based but loosely on Ian Fleming's writings) coming soon. And, Ian Fleming wrote Thunderball based on the film by the same name (per Wikipedia).
Speaking of the most films made based on a single author's works, I have also just read from Pinnacle Books's two-sentence biography on Zane Grey that more than 109 films have been made based on Zane Grey's westerns, an unbroken record. However, let me point out that that statistic is not the same as the largest percentage (nearly 100%) of one's novels being made into films.