A spirited anomaly in modern pop, Sia rejects traditional fame behind oversized wigs while brandishing powerfully expressive vocals across a diverse catalog. Her high-concept videos follow suit, often starring teen dancer Maddie Ziegler since 2014's “Chandelier.” Sia's quirky leanings go way back—watch the rapid-fire Polaroids driving “Breathe Me” or the askew breakup story of “Pictures.”