Sometimes you meet pop groups and they're actually so boring you go off their bloody record while you're talking to them. Other times you meet pop groups and they turn out to be exactly the same as every other pop group you've ever met (this is more common than you might think). On rare and special occasions you meet a pop group who make you laugh out loud with the sheer audacity of the whole thing, a group that have decided that too much is nowhere near enough and that if a thing's worth doing it's worth over-doing so much that the original thing itself gets buried and something even more ludicrous and wonderful and silly and startling comes swimming to the surface. Today is one of those days.

Luke Steele and Nick Littlemore – for they are Australian duo Empire Of The Sun – sit across the table from me. They aren't like most pop groups; for one thing, they haven't played any gigs yet and aren't in any hurry to start, though they dream of a "10-hour extravaganza" in a few years' time. For another thing, they have ambition up the wazoo. In an age where cardigans and spectacles are considered quite a racy combination they have decided to look completely, unashamedly ridiculous (and, therefore, wonderful). According to their MySpace page they have 12,887 billion friends – somehow, this doesn't seem quite enough.

And then there's the music, which slips a softly stroked, super-70s radio-pop satin bomber jacket over some lithe synth'n'drum-machine rocking shoulders (Nick used to be in a band with Pip Ladyhawke - and it shows).

Today Luke is wearing a sort of Chinese hat that appears to have metallic gold branches with tiny mandarins growing on them. His eyes have been enclosed in white rectangles with blue trim, making them look rather like quizzical speech bubbles. He is wearing a long, powder-blue robe ("from Afghanistan", apparently) and white gloves with two fingers removed. To his left sits Nick who is grinning under a huge, black-feathered head-dress. His robe and gloves are also black and his eyes are kohl'd to the nth degree.

"The look is part of the music," says Luke. "Aurally we're like King Crimson standing on the shore playing guitar with the sharpness of Prince's vocal, so that stimulates the ears – but you can't see it, that's where the look comes in."

"The name is so bold that it needs a strong look," says Nick. "We've been travelling through all the places in the world where there had been sun worship, finding out about ancient cultures from Shanghai and Mongolia to Mexico. They are the original empire of the sun."

What have you learned on your travels?

Nick: "Oh, a lot. Like, we need to pay more attention to the natural world and lessen our dependence on technology as it's not making our lives any better. We need to live more simply."

Now, these are fine words and Nick is a very likable sort of bloke, but his call to live more simply is hard to take seriously when he's sat on the seventh floor of a West End nightclub drinking Irish coffee at three in the afternoon while wearing an $800 hat and sporting a "third eye" (trans: gold triangle) on his forehead.

You can't live simply and do this for a job, can you?

Luke: "No you can't."

Nick: "It isn't strictly possible. But we still want to put that message out there for our audience. We want to make the world a better place. We want to channel all the wasted tears towards a useful future. Take the darkness and make it light again."

How's that working out so far?

Nick: "What's important is that we try. People are so driven by money and success, we're trying something else.

Luke: "You've got to keep the dream alive, man!"

Nick: "If everyone in the whole world only ate fruit for two weeks, that would change a lot of things, wouldn't it? We all need to start doing things that don't just follow the beliefs we were brought up with. We need to take chances, make our own art, be imaginative. Look at the shit that's going on in Israel!"

How would you approach that problem?

Nick: "I think firstly people need to realise we're all the same – we all have blood running through our veins. Greed is contrary to our human existence. Greed is the reason so many civilisations have crumbled. You have to be happy with what you've got.

Luke: "We need to bring the romance back!"

Luke Steele is a fascinating chap. His previous project, the Sleepy Jacksons, touched on melancholy country rock and art-punk. He shed a number of members along the way as other musicians realised how hard he was to keep (or, perhaps, put) up with. In late 2003 I interviewed him in Chicago where he told me he wanted to stay on the road forever, only stopping to make a film with Steven Spielberg (interestingly, it was Spielberg who adapted the JG Ballard novel Empire Of The Sun for the big screen). As soon as he finished the tour he met his wife and got married. He now has a daughter called Sunny Tiger and no great desire to get back out on tour. "Back then I was living the big rock dream," he says, "travelling America! I capitalised on sin and debauchery. It was sex, drugs and rock'n'roll …"

You talked of finding someone.

Luke: "Wow! I did, didn't I? I was so lonely then."

You talked a lot about religion too; is that still as important to you?

Luke: "The gospel, the scriptures, the bible – it's the book of life. Christ said, 'Follow me and you'll never fail.' Never!"

That's a pretty big promise.

Luke: "It is, but people don't realise that the spirit of the risen Christ is in everyone – every single person has the holy DNA whether you want it or not. You might as well get used to it!"

Nick: "I'm reading a lot about Buddhism right now. Religions are all interesting, it's good how no one says, 'And lo, all these aliens came down and …'"

Well, there is one "religion" that says that …

Nick: "Ha! Yes there is."

Luke: "Those guys are really out there."

Do they have the holy DNA?

Luke: "Yeeaaahhhhhh!"

Nick: "The truth of it all is that we've put everything into this. That's why the artwork and the costumes and the stories are so big – we're not holding back. We have surrendered all our egos and all our bullshit to get to this point and we're honestly trying to make something better to get to something great."

Have you not made it more difficult for yourself with this look?

Nick: "Maybe, but it's great having a project where you can justify buying an $800 headpiece …"

It's almost like you wanted to buy one anyway and thought you might as well form a band and put it through on expenses.

Nick: "Ha ha ha! Yes, well, you could look at it like that."

I turn off my tape recorder and Nick immediately takes off his head-dress. "That thing is bloody hot," he says, his eyes shining with laughter as Luke quietly sucks on his orange juice, his headwear tinkling.

• Empire Of The Sun's album Walking On A Dream is out now (Virgin)