For directors Huang Jianxin and Zheng, their other goal was to explore and explain how the faith of communism was shaped, hence helping a wider viewership to understand why revolutionary pioneers risked their lives to pursue the rise of China amid the warlords' disunity and foreign oppression.

"The average age of the 13 delegates who took part in the first CPC National Congress was around 28 years old. There were about 50 members when the Party was founded in 1921, and it was those people who had changed the fate of our country," Huang Jianxin says.

"It was also the original impetus to drive us to work on the project for five years," he adds.

In an effort to ensure historical reality, the crew built real-size replicas of the sites of CPC's first and second National Congress and Bowen Girls' School, where the first congress delegates were accommodated for safety concerns.

Besides, some historical details, such as rickshaw license plates from Shanghai－usually each installed with two plates respectively for being allowed to move around the foreign concessions and other areas of the city－are reflected in the film.

With some imagination, based on documents from Chinese and foreign archives and libraries, character arcs are also convincingly developed, according to some critics who saw previews.

Such scenarios include Li Da's romantic moments with his newlywed wife; Mao and several delegates asking a laundry's employee to help them wash the suits they would wear for the National Congress; and He Shuheng, the oldest of the 13 delegates, urging Mao to bid farewell to his wife shortly before their ship sailed from Hunan province for Shanghai.

"The film skillfully blends suspense and history to take a retrospective look at the first batch of CPC members' endeavor to save the nation from subjugation and ensure its survival," says Rao Shuguang, head of the China Film Critics Association.

"It has also updated filmmaking and storytelling techniques for revolutionary features."