WITH the letters JLS painted on their faces, thousands of excited teenage girls fill the Royal Albert Hall. Screaming as loudly as they can, they await the arrival of their (latest) favourite band.

Just seven months earlier, none of the girls had heard of the Londongroup JLS and its members, Aston Merrygold, 21, Marvin Humes, 24, Jonathan "JB" Gill, 22, and Oritse Williams, 22.

But that was before they and 10 million other viewers tuned in to watch series five of TV talent show X Factor last year.

Within a matter of three months the band had gone from pop hopefuls to household names and, with the release of their debut single, Beat Again, this week, have high hopes for their future. But the boys admit that they weren't always so confident.

"It was a goal of ours to get signed, but when we started the show that wasn't our aim," admits JB.

"Our aim was to get through each week. Then, if we did get through to the final, we'd have a one-in-three chance of getting signed."

Eventually, the band finished the TV competition in second place, behind singer Alexandra Burke.

They headed out on a club tour patiently waiting for news from their management as to whether they'd be able to secure a record deal. Newspaper reports of an offer from Simon Cowell's label Syco came and went, and one month later the four received a call.

Marvin recalls: "Our management said, 'You're signed to Epic Records'. We were ecstatic and felt incredibly fortunate."

Their transition from hopefuls to magazine pin-ups has left the boys both amused and excited.

Aston admits: "You can't say you're ever going to get used to girls screaming at you everywhere you go. These days, we get out of a car and for no reason at all girls start screaming. On stage when the vibe is right it can be 10 times as loud. I don't think we're ever going to be ready for that."

As the youngest, shortest and – some would say – most talented of the group, Aston already had huge amounts of public attention.

"I think it's because he's the youngest and he has the little fringe which all the girls like," Marvin jokes. Yet while Aston may receive the most fan mail, the other members aren't short of admirers.

"The younger girls like me, the mums definitely like Marvin, the wild girls like Oritse and the polite, well-mannered girls like JB," Aston explains, matter-of-factly.

But whether the boys will have time to take advantage of being heart-throbs is debatable. While they're all single, Marvin explains: "There's no time to have a relationship. We are busy all the time, so we wouldn't make very good boyfriends. It's hard but we love what we're doing. We'll sacrifice a lot for the band."

The boys have already shown huge commitment to the group. All four gave up careers or university courses to make their pop star dreams a reality.

Oritse, who formed the band in 2007, says he took the selection procedure very seriously. "When you audition a lot of people it's hard because you think, 'Did I let someone go who should be here?' But I made a firm decision. I knew exactly what I was looking for.

"I couldn't have found three better guys. We work well together and we've all got the same mentality. I think it's important in a band to have the same focus and be able to listen to each other."

While Oritse may be the brains behind the bands, Marvin has the most experience. Previously in another band called Vs, the group had three chart singles before being dropped by their label.

He says the experience taught him about the fickle nature of the music industry.

"It put me in good stead for JLS because I learnt so much," says Marvin. "I was the youngest member then and now I'm the oldest in this band."

It's not just Marvin's experiences which are causing the band to be cautious about the future. Apart from a handful of cases, the majority of TV talent show stars have short-lived pop careers.

Aston explains: "We were cautious coming out of the programme and we didn't want to rush the album in case it wasn't the right time. Now we feel we're ready for what we're about to do. We've got a great team behind us and the label know exactly what they're doing."

They couldn't have had a better start, topping Sunday's chart. "It is well-deserved because we have worked so hard," says Marvin.