A co-production between China, Hong Kong and South Korea, the film starred Zhang Hanyu, Deng Chao, Yuan Wenkang, Tang Yan, Wang Baoqiang, Liao Fan, Hu Jun, Ren Quan and Li Naiwen.

In 1948, during the Huaihai Campaign of the Chinese Civil War, Captain Gu Zidi leads the 9th Company of the 139th Regiment of the People's Liberation Army (PLA) to capture a town controlled by the National Revolutionary Army (NRA), during which they sustain heavy casualties from intense enemy firepower.

Upon his release, Gu and his 46 surviving men are sent to defend a coal mine on the bank of the Wen River near Tai'an, Shandong.

PLA forces eventually recapture the area and find Gu, unconscious and heavily wounded, while wearing a NRA uniform he had stolen when he was trapped behind enemy lines.

While Zhao proceeds with his assigned task, Gu, still holding down the landmine, manages to escape but loses his right eye in the ensuing blast.

The caretaker confirms that the bugle call was never sounded because the 9th Company was deliberately sacrificed to buy time for the rest of the regiment.

At this point, he experiences a flashback which reveals that, as enemy forces closed in, he and Wang had buried the bodies of the others deep inside the mine.

While Gu had gone out to continue fighting, a mortally wounded Wang had blown up the entrance to prevent the enemy from capturing the bodies, killing himself in the process.

The PLA erects a monument near the site and conducts a military funeral with full honours for the fallen men of the 9th Company.

The film is also adapted from the novel Guan Si (A Legal Case), which is based on a real-life account of a veteran army captain upholding his company's honour.

Perry Lam gave a mixed review of Assembly in the Hong Kong magazine Muse: "There is a huge discrepancy between the sophistication of the filmmakers in their knowledge and application of state-of-the-art techniques, and the naivety and bad faith they place in the value of unquestioning obedience to authority and sacrifice as the highest manifestation of patriotism.