Zhang Yimou has been hard at work alongside his daughter Zhang Mo shooting his upcoming blockbuster “Sniper,” which is now set for an October release, its production firm said.

The project was explicitly conceived as a nationalistic commemoration of the 70th anniversary of the Korean War, known in China as the “War to Resist U.S. Aggression and Aid Korea.” Although no specific date was set for its debut, it will presumably land in time for the patriotic National Day holiday, which runs from Oct. 1 to Oct. 7 and is one of the best release windows of the year. The timing was announced by Enlight Media CEO Wang Changtian.

“Sniper” is Zhang Yimou’s fourth movie in three years. It is based on the true story of sharpshooter Zhang Taofang, a young army recruit who at age 22 set a record during the Korean War by reportedly killing or wounding 214 American soldiers with 435 shots in just 32 days. He passed away in 2007.

The film will be Zhang Yimou’s most high-profile artistic collaboration yet with his daughter, who is now set to co-direct. She has previously worked with him in editor and assistant director roles on “Coming Home,” “The Flowers of War” and “Under the Hawthorne Tree.” She directed her first feature in 2016: the rom-com “Suddenly Seventeen,” which grossed less than $20 million.

“Sniper” began shooting on Jan. 6 in China’s cold, snowy northeast. “Focus on the War to Resist U.S. Aggression and Aid Korea, repeatedly call out our home country’s memories; Use zealous hearts to salute [veterans]!”, Zhang Yimou’s studio wrote on its official Weibo social media account to mark the occasion. The film was approved for production by censors last October, and has since changed its name from a title that translated to “The Coldest Gun” to its current, more straightforward moniker.

The project has become a bit of a family affair, with Zhang’s young son Zhang Yinan also involved on the crew, shooting by day and taking online classes at night, according to posts from the director’s wife Chen Ting.

Ever prolific, the three-time Oscar nominee Zhang still has two other films that are completed and awaiting theatrical release: “Impasse” and “Under the Light.” His censored Cultural Revolution-era drama “One Second” grossed $20.1 million (RMB131 million) in late November.