Why did Lao Han die on a cliff?

In order not to expose the identity of Zhouyi, he had to commit suicide by taking poison himself. Finally, Lao Han was chased into a dead end to cover Wang Yu's escape. In order not to expose the identity of Zhouyi, he had to commit suicide by taking poison. Above the Cliff is an action suspense movie produced by China Film Co., Ltd., directed by Zhang Yimou and starring Zhang Yi, Amanda, Zhu and Liu Haocun.