With fierce grit and a sure-footed blend of hip-hop and R&B, 2NE1 are an anomaly in the K-pop world. After vaulting onto the scene in 2009 with the taunting bubblegum collaboration “Lollipop” (with BIGBANG), the all-female group blazed forward with the hip-hop-tinged “Fire.” They have continued to forge an unconventional path, delivering futuristic rap over buzzing beats (“I Am the Best”) and throwing out sassy R&B kiss-offs (“I Don't Care”) with powerful vocals, highly danceable rhythms, and an infectiously fun sound.