Pop stars One Direction will be unrecognisable in their new music video after undergoing drastic makeovers.

The boyband is set to release new single Best Song Ever later this month (Jul13), and they have unveiled a teaser for the promo which shows Niall Horan as an old man.

The 19 year old sports a greying beard and thinning hair while wearing a business suit, and other pictures show him sitting in a make-up artist's chair having prosthetics applied to his face.

Each of the bandmates plays a different character in the video, with some of them completely unrecognisable in prosthetics, and the group will unveil more teasers showing the other singers' new looks in the days running up to the song's release in the U.K. on 22 July (13).