Vulcan officer who left the Vulcan ship Sh'vhal for Starfleet because her intuitive thinking clashed with her crew, later joining the Cerritos.
T'Lyn, voiced by Gabrielle Ruiz, is a Vulcan officer introduced in the Lower Decks episode wej Duj as a crew member of the Vulcan ship Sh'vhal. She is as devoted to logic as her crewmates but lets intuition and instinct shape her reasoning, and she stubbornly resists criticism of that approach.
Although her methods often lead to effective solutions, her captain sees her style as incompatible with the crew and transfers her to Starfleet, where her talents are expected to be better valued. In the third season finale, The Stars at Night, she is assigned to the USS Cerritos. There she joins the lower deckers as a colleague and friend, working with Beckett Mariner, Brad Boimler, D'Vana Tendi and Sam Rutherford, and she gradually learns to fit into a less rigid environment while staying true to Vulcan discipline.
T'Lyn's arc is a comic look at the gap between Vulcan culture and Starfleet. She became a regular member of the show's junior ensemble in its later seasons.