Nevala was a female Romulan officer in the 24th century Romulan Star Empire.
In 2374, she was second in command of a squad of Romulans led by Rekar who captured the USS Prometheus, a prototype long-range Starfleet starship. On orders from Rekar, the team killed the whole crew, though Nevala preferred having someone able to help learn the ship's systems.
Unbeknownst to Nevala, The Doctor had been transferred from the USS Voyager and made plans to stop the group along with the Prometheus' EMH Mark II. Nevala brought an injured Romulan of the team to the ship's sickbay and encountered The Doctor, believing his explanation that he was the ship's EMH after a bit of questioning. Rekar and Nevala accepted that The Doctor was doing medical scans on the bridge until he accessed a console. Rekar detained him while Nevala found out that a hologram had been transferred on the ship. She joined Rekar to interrogate him and, when it was apparent he would not admit any information other than a story she didn't believe, she suggested a complete algorithm extraction. She started working on it when she and the other Romulans were rendered unconscious by neurozine gas, introduced into the ventilation system by the EMH Mark II. She was unconscious and captured when the vessel was then returned to Starfleet control. (VOY: "Message in a Bottle")