Here is a blueprint for the career of a successful psychologist who wants to specialise in behavioural pediatrics. A PhD at 24, a spot of clinical research, a job in Los Angeles Children's Hospital running a programme for children with cancer, which leads to the development of a groundbreaking model for psycho-social rehabilitation. Pretty impressive, huh? But wait: there's a twist in the tale. The psychologist in question is Jonathan Kellerman, author of 15 crime novels of which more than 20 million copies are currently in print in two dozen languages. As career paths go, this one might - to the casual observer - seem a tad schizophrenic. Kellerman, though, doesn't think so.
"I was a compulsive writer throughout childhood," he says, "and I've always been interested in human behaviour. As young as nine I'd go to the library and browse around. I grew up in a small suburb of New York, where the local library would allow me to walk around and make a nuisance of myself - and I'd discover these books on psycho pathology, and nobody would really pay any attention, and so I got to read all this totally inappropriate stuff. Which no doubt laid the foundation for my warped mind."
Warped mind? Word association - an image from Kellerman's latest novel, Monster, appears out of nowhere: "Blood smeared the rat-catcher's mouth. His arms were red-drenched to the elbows, his hair and bedding burgundy. Gray-white specks in his hair were found to be human cerebral tissue." I'll spare you the rest - oh, what the heck: there's a missing baby, a tin wastebasket on a hot-plate, a terrible smell. Details that envelop the word "gory" in a whole new colour palette.
But as Kellerman fans will rush to tell you, that's not the whole story. Into the horrific mess will, sooner or later, step Kellerman's regular hero, psychologist Dr Alex Delaware - shrewd, kind, knowledgeable - and his pal Detective Milo Sturgis; wry, gay, competent. A good cop and a good guy. So when Kellerman continues, in his mild, self-deprecating West Coast voice, that "I always wanted to be some sort of doctor; the whole notion of tending to people, caring for people, really appeals to me", you can, actually, believe him.
Still, what he writes about is dark, dark stuff. So dark that when, in 1981, he produced his first Delaware novel, When The Bough Breaks, nobody would publish it. Not because it was no good, but because it touched on a very, very touchy subject. "It was probably the first child-abuse novel," muses Kellerman, "and although it was finally sold in 1983 it wasn't published 'til 1985 because they thought, `what'll we do with this strange book?' " Meanwhile he was tapping away in his garage every night after work, writing an even darker sequel, Blood Test. "Blood Test is a really tough book. When it and When The Bough Breaks became best-sellers, I was absolutely shocked - and so was my publisher."
From being the books nobody wanted to publish, Kellerman's Delaware novels turned into the books everyone wants to read. Not surprising, since they're fast and taut and radiate both a keen intelligence and a sharp sense of humour. And even though Monster is the 14th in the Delaware series - he broke the mould last year with a novel featuring a female cop, Billy Straight - it's as gripping as the first. So did he design his unlikely heroes for the long haul? "I didn't genre-write or - see, the thing about me is, I don't plan in the long term," he says. "I'm not really that ambitious. I kind of drift from thing to thing, and work really hard as I go along.
"Since I didn't come from the English Literature Department, I had no notion of literary versus genre fiction. I just set out to write a certain type of story, and it ended being a crime novel. I was comfortable with Alex Delaware, and I enjoyed writing with him. But if he had been designed for the long haul, I probably wouldn't have written him at all - I mean, to construct a series around a shrink and a gay policeman is not a terribly smart commercial decision. But, thank God, I was so naive I didn't think in those terms."
Delaware, however, was designed to go against the grain of the anti-heroes of crime fiction. "When I sat down to write the book the prevailing hero was the hard-drinking, alienated guy with tons of personal faults and maybe a physical disability or something. And there's still a preoccupation with that - I mean, you'll do a TV movie and you'll have some idiot studio executive saying something like, `well, can't we give him a limp?'. I thought by creating somebody who was basically a good guy with the ability to maintain some sort of stable relationship, I was making a revolutionary statement.
"Which is why I constructed a gay policeman. I thought, another homicide cop - how boring. Let's give him something that will enlarge the character by creating some inherent tension; because, to me, a gay cop in LA is a very difficult thing. No matter how good of a job he does, he'll never be accepted."
Though he was born in New York, Kellerman moved to Los Angeles when he was quite young, and the city itself - another split personality, with its heavenly boulevards and hellish suburbs - is as much a character in his novels as are Delaware and Milo. In fact, in many ways isn't the series a chronicle of a changing city? "LA has certainly changed. When I grew up here, it was a sleepier place. Now it's a big city, with more of the woes of urban life; more traffic, more noise. But on the other hand there's more of the other urban stuff, too - more culture, such as it is in LA; better restaurants; more multi-ethnicity. We've had a recession, we've had race riots, we've had an earthquake."
But the biggest change of all, he says, is the huge growth in the influence of the film industry. "I think it's a negative influence, but it's wonderful from a novelist's perspective because you get great material - it's such a wacky city. I don't think it's a coincidence that some of the finest American crime novels have been set in southern California - I mean, Ross McDonald and Raymond Chandler. And I hope that I'm perceived as being in that tradition."
And what about the tradition that successful crime novels are eventually made into successful movies? "There was," he says, "a television movie of When The Bough Breaks in 1986. It was one of the most successful movies ever made - so of course they never did another one. I had a three-book deal with Francis Ford Coppola to do TV movies; I made quite a bit of money; the movies were never made. That's how you get the best of all worlds, I guess. I actually had some interest from the UK - the people who do the Taggart series were interested in the book Blood Test, but, you know, they talked to me, I said `see what you can do', they never called me back. I got overtures from Germany. They never called me back." Would he think of calling back himself, as it were? "Oh, no. Never. God, that would be suicide. It's very rare for me to even accept an invitation for public speaking. This is the only tour I'm doing for this book; I didn't tour in the US and I signed only once, which was in Manchester. It's very rare for me to deviate from writing. Getting involved in the film business for me would be a tremendous sapping of creative energy and a very masochistic endeavour."
Which doesn't mean he spends all his time in his garage poring over gory details. "I have three very strong interests besides writing. I've been playing guitar for a long time, and I collect musical instruments; I'm a serious painter - not that I want to show my stuff, but I have a studio and I spend a lot of time painting; and I love science. So that keeps me busy. But of course the main thing that keeps me busy is raising four kids and living in a house with another novelist [his wife, Faye]." As for the gory details, he says he reads between 30 and 40 periodicals a month, but not just in forensics and psychology. "I read on art, I read on gardening - I think it's so important for a writer to be interested in history, in culture, in the entire world. Because you never know what you're gonna use. One of my teachers from high school told me: `Jonathan, you were always very curious'. I think it's that curiosity that really helps."
Speaking of curiosity, I'm about 20 pages away from the ending of Monster. I have a couple of theories, but . . . no! Don't tell me! "Oh, absolutely not," promises Kellerman solemnly. "There's always the whodunnit. Although the whodunnit is not really my interest - my interest is the whydunnit. But I always put a heavy whodunnit in my novels, and I always twist and turn them and plot them, because I never cheat the reader. And it's very rare for someone to figure out the ending. Sometimes they figure out some of it, but not" - I can hear the wry grin at the other end of the line - "all of it".
Monster is published by Little, Brown, price £10.99 paperback.