Film actor and director Jiang Wen took his opportunity at the Shanghai International Film Festival this year to promote his upcoming film Hidden Man.

He chaired a forum on June 18 at the SIFF, inviting the creative team of Hidden Man to share their observations and experience of movie making. He then spoke to the media about the film which will be released nationwide on July 13.

He said that as the chairman of the jury of the Golden Goblet Awards of SIFF, what he looked for in a film was signs that a film director "has his own ideas and tells them fluently", adding that he feels humbled being able to judge the blood and sweat of others.

"This could have been the most comfortable time I've had in two years," he said.

The 55-year-old director is well-known for directing Devils on the Doorstep, a film which won him the grand prix award at the 2000 Cannes Film Festival.

Hidden Man, adapted from a novel by Zhang Beihai, tells the story about a young martial arts practitioner seeking revenge in Beijing on the eve of the Japanese invasion. The film is Jiang's third action comedy film set in the early 1900s, and it features gangsters, power grabs, revolution and chaos. The loose trilogy started with Let the Bullets Fly in 2010, followed by Gone with the Bullets in 2014.

Chinese Canadian actor Eddie Peng is one of the leading actors in Hidden Man. The 36-year-old said he enjoyed working with Jiang so much that "you voluntarily bare your heart and soul for the director".

The first installment of the series received acclaim, with box office takings totaling $140 million. The second film, however, received mixed reviews and earned just $83 million.

"I didn't expect Let the Bullets Fly to be so popular with the audience," Jiang told the media during the SIFF. "It was good that the box office income dropped quite a bit for Gone with the Bullets. I didn't have any other choice, but to do everything I could to make the next film a good piece of work," he said.

Jiang read the book Hidden Man almost 10 years ago, but the preliminary screenplay was only completed four years ago as Jiang and his playwrights were constantly honing it.

"People used to say Jiang Wen makes his movies without a screenplay," said Li Fei, one of the playwrights for Hidden Man. "But that's not true. We just kept working on it even during the filming."

"There is always space for improvement, until you capture a scene with your camera," Jiang said.

"If I made a movie of Shakespeare's work, I would have made him sit with me throughout the process."