Zhou also praises the museum's cooperation with the WMF - its first large-scale engagement with the West.
"The Palace Museum has provided an open platform to welcome the most advanced experience and opinions from other countries to help better preserve world heritage," he says.
"The restoration of Juanqinzhai symbolizes cross-cultural exchange and exemplary cooperation in cultural heritage conservation. The project was to bring to life some of the most exquisite arts and crafts created during Emperor Qianlong's reign," says Ted Lipman, CEO of the Robert H. N. Ho Family Foundation, a Hong Kong-based NGO that promotes Chinese arts and culture and is one of the documentary's co-sponsors.
Matthew Hu, project operation director of The Prince's Charities Foundation (China) - the other sponsor - says: "It is our foundation's core notion that these traditional (forms of) craftsmanship are the essence of human civilization and should be passed down to future generations. Not only in China, but globally, it is an integral part of people's cultural identity."
He also points out: "The systematic documentation of this project will not only provide a solid foundation for future research but also help to revive some of the most authentic traditional (forms of) craftsmanship. We hope that experiences learned from this best practice can be followed by many other heritage restoration projects throughout China."
The documentary's executive producer, Andre Singer, says the ability to save such traditional craftsmanship for future generations is a "wonderful achievement".
Zhou says The Emperor's Secret Garden is merely a glimpse at the vast amount of footage he and his crew have shot throughout the years.
He plans to use undistributed footage from previous shoots to create another documentary that will run for at least three episodes, he says.
"The new one will zoom in on details and show the restoration's every step," Zhou says.
"It will also include a strong narrative."
It's expected to air on CCTV and other local channels after it's finished by year-end.
"My spiritual conversation with the Forbidden City will continue," Zhou says.
"It nourishes me."
By Zhang Zixuan