One episode set in Sri Lanka features the protagonist doctor who leads a Chinese medical team to travel around the country performing cataract operations on local patients. The more they see of Sri Lanka, the more they learn about their peers' experience of cornea donations. Around 75 percent of donations in Sri Lanka are pledged by Buddhists, Cui says.

The story is based on real-life events.

In 2014, a project organized by the Chinese government with the support of first lady Peng Liyuan sent a team of Chinese doctors to Sri Lanka to perform 1,000 cataract operations for local patients and to reciprocate the 1,500 cornea donations made by Sri Lankans to Chinese patients.

Yao Xiaoming, an oculist at the Shenzhen Eye Hospital who founded China's first eye bank in Shenzhen in 2000, joined the Chinese medical team on this visit, and now serves as a consultant to the production.

"I heard the story from Yao Xiaoming. It piqued my interest and I traveled to Sri Lanka in October. I was surprised to hear locals I interviewed say they would be willing to donate their corneas after their death," recalls Cui.