Sunken Plum represents the last chapter of the trilogy "Invisible Chengdu", a series of short films set in Sichuan (China) and filmed using the local language of the region, namely Sichuanese. The trilogy reflects aspects of Chengdu's (the capital of Sichuan province) underground scene and includes, in addition to Sunken Plum, the short films Pastèque Amère (2015) and Ni Jing: Thou Shalt Not Steal (2013). Together, these films capture the life and stories of characters that are often discriminated against, the invisible underdogs of society, subsisting in the shadows and nightlife of the city, in a society that it is against the diversity of the population.
The main problem in the location scouting process was to find a village whose neighbors allowed the shooting of scenes relating to funerals. Superstitions, especially those associated with death, are deeply rooted in China. After several unsuccessful attempts, a village was found but located five hours from Chengdu, practically inaccessible due to winding roads and the remoteness of its location in the Sichuan mountains. Even so, all the scenes related to the funeral had to be treated with tact, and in some cases, aspects of the filming process had to be hidden from the villagers.
The dialogue of Sunken Plum is spoken in the Sichuanese language. The use of a local dialect is not new in the career of its directors since in the previous shorts of the trilogy, Ni Jing: Thou Shalt Not Steal (2013) and Pastèque Amère (2015), they deliberately ignored the official Mandarin language in order to use the dialect of the Sichuan province. Similar to their use of the Asturian language in the film Avènement (2016), produced in Spain in 2016. Even though "Sichuanese" enjoys extensive use by more than 260 millions of China's population, and despite the huge differences between "Sichuanese" and "Mandarin", "Sichuanese" has not been elevated to the status of an official "language" and is merely considered to be a "dialect".
Sunken Plum is performed by a cast of non-professional actors. For all of them, the film represented the first appearance in front of the cameras, with the exception of Celia Yinmeng Yu, who already participated in the directors' previous work.
The main role is played by Gu Xiang, who had to build and portray a complex character, Li Wanying, a female transgender facing strong family and social conflicts. To prepare for the role, Gu Xiang worked for several months with the directors ( Roberto F. Canuto and Xiaoxi Xu ) until he got the skills and found the right tone for the character performance.