Juliet Jelenic is a voice actor known for her work in animated feature films. Her entry into professional voice acting occurred with her role in the 2023 computer-animated film, The Super Mario Bros. Movie, based on the popular Nintendo video game franchise.

In The Super Mario Bros. Movie, Juliet Jelenic voices the character Lumalee, a cyan, star-shaped creature known as a Luma. This character is distinctive for its unexpectedly nihilistic and darkly humorous dialogue, which contrasts sharply with its cute and cheerful appearance. Her performance as Lumalee delivers lines that yearn for death and question the point of escape, providing a unique source of comic relief within the film's narrative.

Juliet Jelenic is the daughter of Michael Jelenic, who served as a co-director on The Super Mario Bros. Movie. The circumstances of her casting were unconventional; she was initially brought in to create temporary scratch recordings for the character of Lumalee to assist with storyboarding and animation planning. However, the creative team responded positively to her performance, finding that her voice provided the exact dissonance they were seeking for the character. Ultimately, they decided to use her recordings in the final cut of the film instead of recasting the role with another actor. As of the available information, this remains her sole credited voice acting role, and no subsequent projects or recurring industry collaborations have been documented.