When the young South London quartet The XX burst onto the U.K. music scene with the 2009 single "Crystalised," it was already evident that the group's sleek, dystopian vision of modern soul greatly belied their still tender age (all four members were in their teens at the time). And despite the group's confident cobbling together of influences as far a field as contemporary and classic R&B (Aaliyah, Bobby Womack), atmospheric post-punk (Young Marble Giants, The Cure), and U.K. dance music (dubstep, trip-hop), it was hard to consider them as anything more than the latest hype from hype-crazed U.K. journos. That being said, The XX's 2009 full-length debut is about as fully-formed as first records come, much less ones created by four teenagers. Building upon the alluring vocal partnership of co-leads Oliver Sim and Romy Madley Croft, whose wounded call and response vocals sound mature beyond their years, XX manage to craft haunting synth-fueled melancholia that exudes disillusionment, coy sexuality, and, sometimes, even innocence, all at once. All of which makes THE XX a strong, confident debut from a remarkable young group.