Taken together, the two titles constitute a virtual biography of MacKenzie, former Sun editor and patron of the News Bunny. But MacKenzie won't be pleased with his portrait - not now he's putting himself about as a respectable director at the publicly quoted Mirror Group, with overall responsibility for editorial.
MacKenzie declined to help with the books. "I have tried to meet him many times," says Horrie, 41, who wrote each title with a different co- author. "Kelvin's main concern seems to be that anyone could make any money - even the pitiful sums that one earns as an author of this type of book - as a result of him. But that's hypocritical, because his entire career has been based on other people, not least Diana [Princess of Wales]."
MacKenzie prefers not to comment on having been "monstered" by Horrie, but others don't mind defending themselves. Gary Bushell, one of the few key figures still working at The Sun since Punter was published, says: "Everything they wrote about me was wrong; every single reference to me had some big factual mistake."
That's what he says. But on publication in 1990, Punter was hailed as a devastating expose of the tabloid newspaper that defined the previous decade - and also for providing great entertainment. One reviewer described it as a cross between Waugh's Scoop and Riot on Cell Block 10.
For journalists everywhere, owning a copy was de rigueur. Film rights were sold to Hollywood, where Irwin Winkler used the material for The Paper.
Horrie had already collaborated with co-author Peter Chippindale on a similar book about the Manchester-based News on Sunday, where Horrie edited the colour supplement and Chippindale was news editor. That paper was not a success: "It was a complete cock-up," reflects Horrie. "We had to find a way out, and thought of writing a book about it - about a paper that nobody had ever read, which had come and gone in about two weeks."
Disaster: The Rise and Fall of News on Sunday attracted excellent reviews, and Heinemann duly commissioned Stick It Up Your Punter. They haven't looked back. Horrie subsequently wrote an account of Robert Maxwell's interest in Tottenham Hotspur, Sick as a Parrot, but he continues in his job as director of studies in journalism at the London College of Printing (LCP) in Clerkenwell. Chippindale lives in Cornwall, writing novels.
For L?VE TV, which scrutinises the power struggle between MacKenzie and Janet Street-Porter, Horrie found a new partner, Adam Nathan, a former LCP student. It should be entertaining.
"Just imagine," says Horrie: "Kelvin and Janet is the all-time humdinger. Can you imagine these two characters thrown together? If you put that in a novel people would show you the door. They'd say: 'Does she really have to have teeth like that?'
"And does he really have to say 'bollocks, bollocks, bollocks' all the time?
"When [Punter] was written," he adds, "MacKenzie was hardly known at all, because he deliberately kept a low profile."
That wasn't entirely voluntary. Rupert Murdoch had vetoed TV appearances after MacKenzie's first, disastrous interview with ITN. But for several years MacKenzie had also turned down interviews with print journalists. And yet his influence on Eighties Britain was enormous.
"He was a very important figure," says Horrie. "It was as though we had discovered Cecil Parkinson and revealed that he'd been secretly privatising everything."
In the books, MacKenzie comes across from the start as almost uniquely appalling. Despite failing most exams at school, he turned up at Fleet Street with sufficient self-belief to address senior colleagues like this: "Did you write this f------ stuff? It's all crap!" His approach to editing was similarly ferocious, involving frequent "bollockings" for colleagues - in private, in public, and in the lift. In many ways, he personally represented much that liberal-minded people disliked about The Sun. He would joke in the office about the "gay plague" and "botty burglars". Once, explaining why he didn't watch the film Gandhi to the end, he declared it was "a lot of fucking bollocks about an emaciated coon". Staff found him so difficult that when they were offered redundancy in 1988, 40 journalists applied to go.
And Janet Street-Porter certainly disliked working with him at L!VE TV.
One reason for bringing Punter up to date is the continuing influence across the industry of MacKenzie and the people who worked with him. Proprietor Rupert Murdoch is more powerful than ever, and even MacKenzie's less senior colleagues now hold important jobs, notably David Montgomery and Piers Morgan at Mirror Group. And anyway, much has taken place since 1990: Maxwell's death, Gascoigne's World Cup tears, and MacKenzie's final years at the paper.
Horrie believes credit for The Sun's success should really go to MacKenzie's predecessor. But Larry Lamb has been forgotten, because "he made the terminal error of becoming editor of the Daily Express, and in journalism you're only as good as your last piece of work". Under MacKenzie, adds Horrie, The Sun just became harder and nastier. It became, as he puts it in the book, "the journalistic equivalent of the Sex Pistols, metaphorically gobbing over anyone, or any institution". And sometimes that gobbing went too far. False allegations about Elton John resulted in a front-page apology and record damages of pounds 1m.
MacKenzie personally authorised a picture of a rape victim on the front page, causing outrage across the entire country. And he devised the infamous front page about the Hillsborough disaster (headlined "The Truth"), which alleged all sorts of appalling behaviour by Liverpool fans. On Merseyside, copies of the paper were burned on the streets and sales slumped dramatically.
Horrie is full of praise for good tabloid journalism, but these incidents, he says, were unforgivable.
"Kelvin's argument is that there are 50 stories in the paper each day, and he edited the paper for 12 years, so he's bound to get a few wrong. But you can't write off Hillsborough as a bad day at the office. That's a bit like an airline pilot saying, 'OK, I crashed and killed everyone, but what about all those times I took off all right?'"
So what will Horrie tell us about The Sun's performance since MacKenzie's departure? The book's subtitle, The Rise and Fall of The Sun, originally bothered some readers. "People used to criticise us and say, 'what fall?'" But the passing of time has shown the paper's decline more clearly. Not only have sales dropped, but The Sun has also lost its pizzazz.
The current editor, Stuart Higgins, wins measured praise. "People say he is a perfectly straightforward, honest tabloid journalist," says Horrie.
"He's about my age, from the generation that finds it embarrassing to be sexist, and takes women more seriously."
Even Higgins, however, must answer for several excesses. "His main claim to fame," Horrie explains, "was a line into Camilla [Parker-Bowles]. So every time Diana gave some story to the Mail, Camilla would pop up with Higgy, saying Diana was mad and having affairs. Some of the stuff The Sun ran about Diana in 1994, '95 and '96 was unbelievable."
All the same, Higgins need not fear too fierce a roasting. In the final analysis, pronounces Horrie, "Higgins is not as entertaining as MacKenzie."Reuse content