The Penis on Legs – aka Piers Morgan – is resiliently handling my barrage of offensive, tabloid questions. It’s just as well that he’s so robust, since two days after we meet he gets fired again; only this time it’s for charity, Comic Relief’s celebrity The Apprentice, where we see Morgan enjoyably insulted by Maureen Lipman (responsible for the aforementioned penis gibe) and Alastair Campbell, and later, Graham Norton’s “Piers Morgan – what an easy person to hate” is greeted by whooping cheers from the audience.

The timing of this panto-villain acclaim is highly convenient for the latest chapter in the saga of Morgan’s entertaining career – as the former “shamed” Daily Mirror editor (to give him the treatment his old paper meted out to the likes of Peter Mandelson) prepares to become a boo-hiss judge on Simon Cowell’s Britain’s Got Talent, having already wowed America on the US version of the show.

The latter – involving “zany” acts such as granny rappers and men who put scorpions down their trousers or kick themselves in the head – has been a huge hit Stateside (number one in the ratings last summer for the NBC network, attracting more than 14 million viewers) and Morgan has found himself recognised on the streets of Beverly Hills and – joy of joys – “papped” frolicking in the surf with his girlfriend (gorgeous!/glamorous!/posh totty!/blonde bombshell-with-brains!), the Telegraph’s gossip columnist, Celia Walden.

Never one to suffer self-doubt, Morgan predicts that Britain’s Got Talent, unleashed this summer, will be equally huge… more weirdo acts and a more savage audience made up of strangers from the street, “It’s like a Roman amphitheatre where someone will start an act and suddenly the mob will start screaming, ‘Off, off, off’ and it’s crazy! And Cowell holds his hand over the buzzer like a Roman emperor asking, ‘Should he live or should he die?’ and the crowd starts chanting, ‘Press it, press it, press it’, and he looks around, smirks and goes boom and that’s it. Cowell came out of the first day of auditions and said it was the best television he’d ever been involved with – completely crazy, I mean, hilarious! And with Ant and Dec presenting and Simon Cowell and Amanda Holden and me on the judging panel…”

So would you say that it’s downmarket? “Er – it’s not upmarket. I don’t think it claims to be Newsnight in a different guise, no. But is it damn good entertainment? Yes. Is it fun to judge? Yes.” Do you feel a bit moronic doing it? “No, because I’ve never worried about being taken seriously…” It’s quite an odd move after… (Morgan’s anti-war campaigning years on the Mirror when he hired heavyweight writers such as Jonathan Freedland, John Pilger and Christopher Hitchens, and won the sort of awards which are usually reserved for the top end of the market). “Not really,” he says, anticipating where my question’s going. “If you’re the editor of a tabloid newspaper, you’re not really saying, ‘I want to be taken seriously’.”

What he’s learnt about television is that it’s all theatre “whether you’re Jeremy Paxman on Newsnight or Simon Cowell on The X Factor – one is very intellectual, the other isn’t, but I believe they’re both thinking, ‘How can I make this work from a televisual point of view’, and I’d say that if you’re looking at quick-wittedness and sharpness of wit, they’d both go head-to-head. I’ve never sought to be, you know, a serious intellectual and I don’t claim to be massively well-read, although I’m reading a lot more now and I’m enjoying it – but I don’t think I’ve ever been stupid and I’ve always tried to be open to anything and I’m interested in people and events.”

Here’s a confession: some people actually don’t find it easy to hate Morgan and I’m one of them. He was only 28 when Rupert Murdoch promoted him from Bizarre showbiz columnist on The Sun to editor of the News of the World (the youngest national newspaper editor for more than half a century), and much like the boy bands he used to dish the dirt on, Boy Morgan had to do his growing up in public. He made plenty of indefensible mistakes and had his knuckles duly rapped (for instance, when he published photographs of Victoria Spencer leaving a detox clinic). He continued to make them when he became editor at the Mirror (the ACHTUNG SURRENDER headline on the eve of the England v Germany Euro ’96 semi-final; the Viglen shares scandal of 2000 which dragged on for four years with Morgan eventually cleared while his City Slicker columnists were fired; culminating in the publication of the hoax photographs of British soldiers abusing Iraqi prisoners which finally did for him).

Morgan’s adventures in the tabloid world were revealed in his first bestseller, The Insider – a rattling good read, fascinating for its glimpse into just how much power a red-top editor can wield with the great and the good (so many visits to No 10; so many e-mails from Peter Mandelson), but also riveting for its self-penned portrait of the author as a sort of Artful Dodger happily nicking scoops from his senior colleagues, playing fast and loose with the truth, distorting celebrity photographs and so on, if it suits him.

But it’s not all harmless high jinks, as Morgan discovers only when his own marriage difficulties are written about in other publications, and he finds himself growing up rather abruptly. These personal complications coincided with the build-up to the Iraq War and suddenly Morgan was a man with a mission – the Mirror was to transform itself into a tabloid with a conscience, reconnecting itself with the pre-Maxwell-Cudlipp era, taking on governments rather than bothering itself with the minor peccadilloes of B-list celebrities. His anti-war campaign there lasted for two years, during which time the circulation went into freefall and he was eventually sacked.

Even during his glory days Morgan was still capable of behaving unattractively, to put it mildly. There were his petty, long-running feuds with Private Eye editor Ian Hislop (against whom he launched a campaign in the Mirror, thereby making himself look both vindictive and ridiculous); ditto David Yelland, then editor of The Sun – and that strange business with Jeremy Clarkson, who decked him for printing photographs of him kissing a woman other than his wife. All of it to do, rather loweringly, with either being exposed or exposing – and none of it showing anyone in a particularly good light.

So what’s there to like? Not a lot, if your only experience of Morgan is through his TV appearances. Television may be Morgan’s new career, but it does not flatter him. He has certainly improved since his early excruciating performance on Have I Got News for You, but he can still seem horribly pleased with himself, bumptious, brash, arrogant, tub-thumping and generally not someone you’d want to spend any time with.

But off the screen, on the few occasions I’ve bumped into him, he is smart (as opposed to a smart aleck), funny and generous-spirited. He can be immensely charming, and his character makes a great deal more sense when I discover that he’s Irish on both sides of his family (the Pughe-Morgan double-barrel is from his Welsh stepfather, who brought him up, rather than evidence of plummy landowning stock). I happen to know that he has been helpful to all sorts of organisations without reaping any personal reward or kudos, and he’s naturally meritocratic, trebling or quadrupling the number of women journalists on the Mirror as well as hiring people from ethnic minorities. This is one of the things he’s proudest of in his journalistic career, alongside his editorship of the paper after 9/11.

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