With the increasing importance of the mass media in social life and the linguistic changes it incurs, sociolinguistic research on linguistic representations in cinematic discourse has been increasing recently. Situated within this growing body of emerging scholarship in sociolinguistics, this study examines how Korean immigrant English is represented in a Canadian TV sitcom, Kim’s Convenience. Drawing on the perspective that linguistic performances in fictional discourse serve as resources for sociolinguistic styling and characterization, this paper investigates how the linguistic representations of Korean immigrant English contribute to authenticating the character of a middle-aged male Korean immigrant called Appa in the TV series. For this purpose, Appa's English used throughout the TV series' first season (13 episodes) was analyzed at the phonological, syntactic, lexical, thematic, and semiotic levels. The analysis revealed that each linguistic level shows distinct but concerted efforts regarding the authentication of Appa as a Korean immigrant. The phonological features of his English effectively share those of Korean English, whereas the syntactic representations are characteristic of a simple register. The lexical, thematic, and semiotic representations additionally reinforce Appa's “Koreanness” through the sitcom's integration of topics and images related to Korean culture.