A poster for the movie Sky Stream, with protagonist Huang Dafa played by actor Zheng Qiang. [Photo provided to China Daily]

Then, when he gets tired, he tells his son to continue, saying: "If you do this, I do not have to seek compensation even if something happens to you."

Speaking about the film, Zheng Qiang, the actor who plays Huang, says: "As a father, I was shocked to read this in the script."

According to Bo, when Huang was invited to watch the film for the first time he found it rather emotionally demanding. The film will be released in mainland theaters in September.

"I hope the spirit of Huang will be passed on through this film," says Bo.

Contact the writers through wangru1@chinadaily.com.cn