Tabatha Brisk was the former Chief Medical Officer aboard the ISS Arcadia in the mirror universe. Like most Terrans, she was born into slavery, but was adopted as a child into one of the "privileged" Terran families who enjoyed higher social status over other Terrans in the Klingon-Cardassian Alliance, allowing her to learn medical knowledge and become a doctor. Wooed by Stephen April, she joined the rebellion against the Alliance and played a formative role in the new Empire's organization, with regards to medical programs for the new Starfleet.
Among April's "women", Brisk was his "primary" partner aboard the Arcadia, a position she strived to maintain, making her privy to many of April's secrets. However, like her primary universe counterpart, she was compassionate by nature (a weakness in the mirror universe), and although loyal to April, grew dissatisfied with life aboard the Arcadia. In 2385, after an assault upon her person by Jackson Bretta, she transferred to the ISS Corregidor.