Inner Mongolian musician Khalamj. [Photo/Benteng Integrated Media]

Box office sensation Ne Zha: Demon Child Conquers the Sea (Ne Zha 2) has topped China's all-time movie box office rankings. Beyond its compelling story and stunning visuals, the film's soundtrack has also captivated audiences, with a unique sound from the depths of the grasslands that surprises listeners.

When the Tianyuan Cauldron celestial artifact appeared on screen, a deep, roaring sound resembling howling wind and rumbling thunder erupted. Though its meaning was unclear, its grandeur was undeniable. This distinctive musical element originates from Inner Mongolia's "Khoomei", or throat singing.

When first hearing Khoomei, some mistook it for an electronic sound effect. In reality, it is a unique vocal technique in which a singer produces two tones simultaneously – a fundamental drone and an overtone melody. This ancient art has been passed down through generations on the Mongolian grasslands for over 1,000 years.

In 2006, Khoomei was listed among China's first National Intangible Cultural Heritage batch. In 2009, UNESCO recognized Chinese Mongolian Khoomei on its Representative List of the Intangible Cultural Heritage of Humanity.

Today, young musicians are revitalizing this traditional art form, with rising Inner Mongolian musician Khalamj from Bayannuur performing the Khoomei vocals in Ne Zha 2. He was invited to record for the film around December last year.

"I had watched the first film, which set a record for Chinese animated movies, so being part of the sequel was incredibly exciting", Khalamj said.

"There are so many people in China and around the world. I'd be thrilled if this movie helped introduce Khoomei to more audiences. And if it inspires a deeper appreciation for the art, I'd be even happier", he added.