This content is copyright of CelebMix.com. XO are back - and they're not just returning, they're staking their claim, stepping into a sharper, more self-assured era that makes it clear they're done circling the spotlight and ready to stand firmly at its centre. Made up of Emmy, Reanna, Shali, Summer and Zoe, the rising British girl group lean all the way into their electrifying pop instincts on 'Hotline', crafting a slick, high-gloss anthem that pulses with confidence, razor-sharp hooks, and a knowing sense of attitude.