Every new pop act needs an undeniable, globe-straddling debut single and One Direction's arrived in the shape of “What Makes You Beautiful,” the power-pop jewel in their debut album’s crown. Its youthful abandon permeates what follows, specifically the carefree yearning of “One Thing” and the more succinct “I Want.” “Gotta Be You,” meanwhile, hints at the more earnest love songs that would become the band’s trademark. Mixing elements of rock into the pop palette, Up All Night helped redefine the aughts' boy-band template.