This study investigates Chinese-English code-mixing in the film Everything Everywhere All at Once (2022), focusing specifically on insertion as theorized by Muysken (2000). It examines how insertional code-mixing in scripted multilingual dialogue functions as a narrative strategy to convey identity, emotion, and cultural hybridity in diasporic contexts. Using a qualitative descriptive method, data were drawn from manually transcribed utterances inMandarin, Cantonese, and English. Analysis applied Muysken’s typology alongside Halliday’s sociopragmatics framework to interpret the pragmatic and social factors underlying the insertions. A total of twenty-nine insertions were identified and categorized into phrasal or clause insertions (48.28%), discourse features (41.38%), and lexical items (10.34%). Phrasal and clause insertions most frequently occurred in emotionally intense scenes, expressing affect, authority, or familial conflict. Discourse features such as interjections served to convey emotion and establish shared cultural understanding, while lexical functioned as cultural markers rooted in tradition. The findings demonstrate that insertional code-mixing is a deliberate narrative tool that enhances character depth, cultural resonance, and cinematic authenticity. This study contributes to a broader understanding of how multilingual media can represent bilingual subjectivity, challenge monolingual norms, and reflect complex sociocultural identities. By linking linguistic analysis with filmic representation, the research highlights the significance of studying multilingual cinema as a site where language, identity, and emotion intersect in diasporic storytelling.