The doctors checking the wards every day also take the role of "messengers". Sometimes, members of the same family get infected and are quarantined in separate rooms. As they cannot contact each other, doctors will ferry news and messages back and forth between them.

"In the most dangerous place, you'll find the warmest part of humanity," Kang continues. "It's easy to be influenced by this atmosphere, one that can encourage us to be better people in the future."

However well they are prepared for filming, on the wards, unexpected situations arise from time to time. They have to remain alert to capture the touching moments.

Kang recalls that, one time, a group of doctors became excited when they heard that a patient, who was in coma, began to cough. However, less than three minutes later, Adrenalin was high as they were forced to react to another patient whose heartbeat had stopped. When that patient was stabilized, following a five-minute cardiac resuscitation, the doctors were too exhausted to even speak.

"But I saw tears in some of their eyes," Kang says. "The destiny of life and death is often determined in minutes. For me, this will be a lifetime memory."

Filming began as the campaign against the virus was at its toughest point, and the crew was able to capture the stories of many of the medical teams from across the nation who headed to the city to help.

Now, as the outbreak is brought under control and makeshift hospitals are finally closed, the crew also films some of them as they prepare to withdraw from Wuhan.

"When a medical team is leaving, the last member getting on the bus notices that we are shooting," Cao, the field producer, says. "They often ask the driver to open the door, get off the bus and come over to say hello to us."

For that reason, he wants to present the documentary to the "heroes without halos".

However, Xu Lyuye, a doctor based in Wuhan, told Cao: "I don't think I'm a hero. It's just my job. If it was your job, would you avoid it? Everyone just wants to do their duty."

Though Zhang, the executive producer, does not reveal the specific stories being told in the remaining two episodes of Dong Qu Chun Gui, he reveals that they will cover cities other than Wuhan, including metropolises like Beijing and Shanghai and smaller cities like Nantong in Jiangsu province, to reflect how the lives of Chinese people all over the country have changed because of these extraordinary circumstances.

Additionally, Youku also has crews in the United States and Africa who will record how people in those countries are fighting against the coronavirus pandemic.

"When we launched the project, we didn't expect novel coronavirus to become a pandemic," Zhang says. "We only thought it might be better to include an overseas perspective. However, the current situation in the world proves the global significance of a joint effort."

As for the crew in Wuhan, they have to stay in the city for a while longer, and not just because of the quarantine regulations.

"I believe there are many more stories in the city which are worth telling," Zhang says. "We want to follow-up and record how people in the city recover, physically and psychologically, and how local society will resume."

Since spring has finally arrived, perhaps, that day is not too far away.