Lissan was a member of the Aenar. In 2154, when Andorian Commander Shran and Starfleet Captain Jonathan Archer visited Andoria, Lissan was assigned to act as Speaker for her species. Archer allowed her to read his mind so she could understand that one of the Aenar, Gareb, who had been kidnapped by the Romulans, was telepathically piloting the ship attacking Enterprise NX-01. She believed that the evidence that had been gathered to prove that an Aenar was in control of the Romulan drone ship appeared irrefutable. She was shocked that one of her species had caused so many deaths.
In a room within the Aenar city, Archer attempted to convince Lissan to help them destroy the Romulan drone ship. She told him that the Aenar wouldn't participate in the use of violence because they were a pacifist race.
After Jhamel, sister of Gareb, offered to help, Lissan used her telepathy to confuse them so they could not find the way to the surface. Later, a holographic representation of Lissan appeared in a tunnel opening before the group and tried to convince Jhamel to return to the underground city. Using her telepathic ability, she discovered that Jhamel wanted to help her brother. Lissan allowed them to leave. (ENT: "The Aenar")