In 2017, after a stint as a TV director, when Pan was considering making his first film, he naturally wanted to work on something that he was most familiar with and attached to.

"It's meaningful if I can present the faces of those film stars from 40 or 50 years ago on the big screen today," he says. "I want to show their professionalism and pure love for the art of acting."

After an 18-month struggle with investment, Pan interviewed nearly 100 artists aged 80 and above. He originally gave the documentary the name Chuxin (Original Aspiration).

In 2019, the film team decided to change the title to Yanyuan, shifting the focus onto the 22 film stars in the early 1960s, a vibrant period for the Chinese film industry.

"The works of these 22 artists have touched audiences for generations, and their film characters have become classics. Over the decades, they have still maintained their passion for film and are still role models as artists and people," he says.

However, as many of them have died, the documentary features just eight of them, in addition to other actors and actresses.

One particular touching moment of the documentary is when one of the interviewees Zhang Jianyou, an actor in The Battle of Triangle Hill, could not hold back his tears.

In April 1956, three years after the end of the War to Resist US Aggression and Aid Korea (1950-53), a cast of more than 100 people went to the Democratic People's Republic of Korea to visit Triangle Hill in person for the making of a film about the ferocious battle. Before they reached the hill, the views were so good that people were all happy.

However, when they arrived at the battlefield, they were shocked to see not a single green tree in sight because in the 43 days from Oct 14 to Nov 25, 1952, shellfire had obliterated the landscape.