Cataracts are one of the most frequent causes of visual impairment worldwide. The disease leads to a clouding of the eye's lens, which affects sight. Left untreated, cataracts can ultimately lead to blindness. Although surgery to remedy the problem is straightforward, access to ophthalmological services is limited in lower-income countries.

Sanduk Ruit has devoted his life to healing as many cataracts sufferers as possible. The Nepalese doctor, who himself comes from a modest background, wants to ensure high-quality surgery for patients living in grinding poverty — even where there is no hospital in the vicinity. The 70-year-old and his team have now treated well over 100,000 people with cataracts.

This documentary accompanies Sanduk Ruit to an extremely remote region of the Himalayan Mountains, where every 12 years the Dolpo region of Nepal hosts the Shey Festival at an elevation of over 4,000 meters. It's a centuries-old cultural event, which is rooted in Tibetan Buddhism and draws people from far and wide — and for the doctor, a perfect opportunity to treat a large number of patients in one location.

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