Aqua made a splash in the '90s with the giggly, glittery “Barbie Girl,” which packaged its sly poke at gender norms with an energetic beat and irresistible chorus. The contrast between Lene Nystrøm's candy-coated soprano and René Dif's gruff growl adds a shot of playfulness to that and other dance-floor-ready tracks like the house-tinged “Lollipop (Candyman)” and the hyperactive “My Oh My.” Ballads such as the sumptuous “Turn Back Time” and the pensive “My Mamma Said” showcase Nystrøm's vocal range, as well as the moodiness that can offset the group's high-gloss pop.