MORE than two decades ago, Harry Hill left the world of medicine for comedy in order to pursue a less 'obvious' career path - and he hasn't looked back since. But that's not to say it's always been an easy road, he tells Gemma Dunn.

From Alison Hammond and Sir Tom Courtenay to Chris Packham and The Krankies, the line-up on Harry Hill's Alien Fun Capsule may read like a bizarre dinner party guest list - but it's how the host likes it.

Returning for a third series, the comedy panel show - a firm favourite with ITV viewers - will once again see the bespectacled comedian preside over two teams of celebrities, each tasked with saving Planet Earth.

While previous seasons have included the likes of Kathy Burke, Alex Brooker, Lorraine Kelly and Moira Stewart, this run promises another unlikely blend of stars, from the aforementioned foursome to Bill Roache, Charlie Dimmock, Amanda Barrie and Pam St Clement.

"What I like to do is mix up guests that you wouldn't necessarily see together," reasons Hill, 54.

"We've got some good people and we've got some of my favourite newer comics too: Josh Widdicombe, if you can still call him new, and Tom Allen, who I'm a big fan of."

And hailing it the best yet ("I think the first couple of series, it takes a little while to work out what the show is"), what can fans expect from another run?

"The first half is mainly me just taking the mickey out of the guests, playing funny clips of them from their past," Hill chimes. "Martine McCutcheon's long-lost exercise video and Nick Helm on Mastermind...

"And then in the second half there's some sort of stupid, contrived competition or project; and then it finishes on a song. So there's lots of fun and there's lots within the [episodes]."

It's a formula Hill has come to love.

"There's something about playing clips of people to the people," he notes. "So we've got a clip of Stephanie Beacham in some crazy outfit and playing that to her and seeing her reaction makes it doubly funny!

"It's also that thing of surprising guests and getting them to do silly stuff, which is not really something that I'd done before," he muses. "TV Burp was pretty much just me, as, although we had guests, they weren't celebrities on the whole.

"The fun thing in TV is to do something different and learn new bits," he maintains. "And there's enough familiar of what I do on the show, but there's some new bits too. It's a challenge."

How well does he think the world would cope with an alien invasion, then?

"I kind of think we could do with one right now, to sort us out," quips the longtime You've Been Framed narrator. "Maybe that's the answer?

"There is one theory that they're already here, but it depends who you believe," he continues. "I grew up in the 70s and we were all obsessed with UFOs - every day the papers would print another photo of a flying saucer," he remembers.

"You don't get it so much now, but that kind of stayed with me a bit."

It's not all extra-terrestrial for Hill, however. The Woking-born presenter - real name Matthew Keith Hall - previously trained as a medical doctor, but found his way into comedy having won the Perrier Award for Best Newcomer at the 1992 Edinburgh Fringe Festival.

This was followed by a stint on the radio with Harry Hill's Fruit Corner, and eventually the now iconic TV Burp, which made a splash on Saturday-night prime-time telly for an 11-year stretch.

It's a far cry from his one-time ambition, Hill realises.

"I worked for about two years full-time and then for about 18 months part-time," he says of his former medical path. "But I've got friends who stuck at it, so I can see what I would have been."

"That was part of the reason I gave up: I could see my whole life planned out ahead of me, it was a bit too obvious," confides Hill, who claims he manages to fly under the radar in public if he's not donning his tell-tale big collar.

"I'd probably be a GP in Kent, or a psychiatrist, I don't know! Or I'd probably be struck off, is the truth, for making some medical mistake," he jokes. "Now all my friends are trying to retire, they all want out."

But while his subsequent showbiz success is plain to see, he's not about to encourage others to follow suit - especially his children.

"I have three, all girls," he says. "They're all funny in their own way, but I never kind of encouraged them to [get into comedy].

"I didn't want them to get into it just because it looked like fun; if you want to succeed in what you've always loosely called 'showbiz', you have to be really dogged about it," he states. "Otherwise I think it can be quite a miserable life.

"I didn't want to feel like I was pushing them into it or making it look easy, because it's not so easy."

In fact, if his "friends who are younger comedians" are to be believed, now it's trickier than ever to forge a career in his industry.

"They tell me it's a hell of a lot harder at the basic club level, which is where everyone develops their skills, and there's not much money around," he explains.

"It's difficult to make a living out of it, and if you can't, it's difficult to pursue it," he adds. "I also think there's a lot more people wanting to do it; I don't know why.

"When I started doing it, it wasn't a particularly acceptable thing to say you were doing. You could say, 'I'm going to go to drama school and be an actor, Mum', but you couldn't really say, 'I'm going to be a stand-up comedian, Mum.'

"It was a weird thing, a dirty secret, but I think maybe it's become more acceptable now," he ponders, admitting that the circuit - and rightly so - is more diverse than ever.

"I'm all for it, really. I think there's room for everyone and the fact is people who aren't that funny don't get on. They only last a little while."

He follows: "The tough thing really is to stick it out. I haven't quite done it, but if I make it through to 60, then I probably would have done it.

"But it's been great," he finishes. "And having come from medicine, which is a really serious thing, I thank my lucky stars I've always managed to make a living out of it."

Harry Hill's Alien Fun Capsule returns to ITV on Saturday June 8.