The transformation of those who returned can be inspiring for today's young people, he says. "I hope their stories encourage younger generations to pay less attention to material life and shoulder more responsibility in China's rejuvenation."

To attempt a vivid re-creation, the documentary team traveled to Paris, Normandy, Lille, Lyon and other parts of France, visiting archives, schools, universities, museums and historical sites. Valuable records, including lists of registered students, such as Zhou, Deng and Nie, and recordings of an interview with Xiao San, a Chinese student who traveled from Hebei province to Montargis for higher education, are shown in the documentary.

The production team interviewed more than 30 offspring of the program's participants to gather their personal memories and views on what their forebears experienced during their time in France, before searching for ways to save their homeland.

Tao says that these personal perspectives provide a broader picture of the past.

"Their emotional expressions give a warm touch to the history and generate empathy among viewers," he says.

Chi Jianxin, the documentary's producer, says: "We try to reproduce the spirit of that age and evoke memories of yesteryear by portraying images of the Chinese students. It makes us understand from where we have come, and the direction we should go."

Tao says his team will work on a follow-up documentary. They will present more stories that reveal the twists and turns in the lives of these Chinese pioneers by collaborating with research institutions and museums that were built in commemoration of the work-study program.