In the mirror universe, Marlena Moreau was a Human female who served as a scientist aboard the ISS Enterprise. By 2267, Moreau had also became James T. Kirk's "captain's woman". As the "captain's woman" she was privilege to some of Kirk's darkest secrets, including knowledge about the deadly Tantalus field which had helped him to retain command of the Enterprise. During the crossover incident which saw several crewmembers (including Kirk) being swapped with their primary universe counterparts, Moreau assisted James T. Kirk in overcoming Hikaru Sulu's assassination attempt by using the Tantalus field to eliminate his henchmen. She then assisted Commander Spock in returning the counterparts to their proper reality. (TOS: "Mirror, Mirror")