When the Barbie Rainbow Lights Mermaid doll is submerged in water, her mermaid tail will sparkle with vibrant lights that mimic a glittering rainbow. To turn Barbie’s light show on, press the button on her necklace and immerse her in the bathtub or swimming pool. Bring the magic to land: without water, you may enjoy the light display by pressing the button on the doll’s necklace. The entire enchanted mermaid ensemble is completed with rainbow fins, a royal headpiece, pink-streaked hair, and a belt adorned with “pearls.”