The rogue Leviathan was a Leviathan ship that attacked Moya when she attempted to bury Talyn's remains in the sacred Leviathan burial space. The rogue Leviathan's last three offspring were captured and enslaved by Peacekeepers, which had driven her mad with grief and inspired in her a desperate hatred of all things Peacekeeper. As a result, when Moya wanted to bury her half-Peacekeeper-gunship child in the sacred space, the rogue Leviathan went berserk and attacked her.
Although Moya's crew first considered leaving peacefully, Moya was determined that Talyn be buried alongside his ancestors, and learning that the rogue Leviathan had deprived her own Pilot of nutrients, starving him to death, only enforcing her determination. Soon Moya learned that the rogue Leviathan had attacked other Leviathans before her, killing three and injuring more, this was proof that the Leviathan had gone completely insane. Moya, having gone through the heartbreak of losing a child herself, knew that the rogue had gone too far and asked her crew to kill the rogue Leviathan.
As Moya dove forward into the sacred burial space, Aeryn Sun and Ka D'Argo and John Crichton deployed from her, Aeryn in her Prowler, D'Argo and Crichton in the ship Lo'La. Aeryn fired on the rogue Leviathan, distracting her long enough for D'Argo to get a clean shot at her with Lo'La – and one shot was all it took. The blast disintegrated the rogue Leviathan into dust, finally ending her reign of insanity over the sacred Leviathan burial space. ("Dog with Two Bones")