JLS in behind-the-scenes look at 'Hottest Girl in the World' video
The boyband will release 'Hottest Girl in the World' on October 21 as the lead single from their fourth studio album Evolution.
"We wrote this song about three months ago now and, the track, we want it to [represent] the new sound of our album really," Marvin Humes explained.
"It's definitely a bit harder, it's a bit more R&B and the beats are heavier."
JLS will release their new album Evolution on November 5 and previously said that the record "felt right".
"We're very excited about it and this is the album we wanted to make, we wanted to make this for our fans," they said.
"We didn't go by any kind of guidelines or anything like that, we just made what felt right and we're really excited about it!"