The total box office of the 2024 Spring Festival has already surpassed that of the same period last year on the sixth day of the year. In this comedy based film season, director Zhang Yimou's main theme film "Article 20" participated in the competition of the Spring Festival season with a different attitude. It explained the serious "legal theme" with a seemingly comedic background, presented the complex aspects of grassroots legal work in China, and completed an important legal education campaign. More importantly, as a main theme film, "Article 20" provides a serious "review" and "correction" of the conviction and sentencing of Article 20 of the Criminal Law on "justifiable defense" from the perspective of the procuratorate in the past legal work. This is rare in the theme expression of mainstream movies in the past decade. As a main theme film, its function is to promote the mainstream ideological level, and in Article 20, it also includes the popularization of legal concepts and specific elements of legal provisions, and completes the expression of the "legal theme". The following will analyze how Article 20 artistically expresses the theme of the rule of law from different perspectives. In terms of ideology, Article 20 focuses on the development process of legal awareness and legal provisions on "legitimate defense". The legal consciousness in the concept of Article 20 is reflected in the following two aspects: the "resistance consciousness" at the role level and the "self correction consciousness" at the theme level. The "resistance consciousness" of movie characters plays a driving role in the play and is one of the psychological motivations for characters to achieve their goals. In the film, Lv Lingling is portrayed as a female prosecutor with a strong sense of resistance. She argues with reason, adheres to principles, and maintains a rigorous attitude towards handling cases in the face of criticism from her superiors. In the end, the knife, which serves as key evidence, is found, and the suspense of the drama is also overcome. And another character in this film, Han Ming, as a public security, procuratorial, and legal personnel, bravely expressed his view that the nature of the case belongs to "legitimate defense" in the past when cases were considered "intentional injury" or "intentional murder" in precedents. This not only completed the shaping of the character's arc, but also further deepened the theme through the arc of human and object: in the face of unreasonable situations, one should be brave enough to point out problems and bravely solve them. This simple truth is presented on the one hand through character transformation. On the other hand, countless examples both inside and outside the play have already shown us the difficulty of this path. But it is precisely with the presence of prosecutors such as Lv Lingling and Han Ming that the progress of China's legal system is possible, and behind all the difficulties lies the brilliance of human nature and the rule of law. The theme of "self correction consciousness" is actually the highest level of "self correction consciousness", which is reflected in the review and correction of the erroneous application process of legal provisions on "legitimate defense". Article 20 presents the unreasonable aspects of conviction and sentencing in the past, and finally explains the relevant legal progress. As early as 2009, the Deng Yujiao case sparked a broad and in-depth discussion on Article 20, but this did not change the judicial authorities' understanding and application of Article 20. In the film, there are also presentations of these errors, such as Han Ming and L ü Lingling arguing and presenting multiple judgments from 2009 onwards, all of which were convicted of intentional injury or even more serious charges after the lawyer pleaded not guilty. such