In the mirror universe, Admiral Lance Cartwright was a Terran admiral serving in the Imperial Starfleet of the Terran Empire during the late 23rd century. He was part of a military cabal to assassinate Emperor Spock. The cabal also included Colonel Ivan West, Admiral Thomas Morrow, General Quinven of Denobula, and Admirals Robert Bennett, and Salliserra zh'Ferro. They were planning to assassinate him by having Valeris, an assassin, infiltrate the Emperor's elite Vulcan Guard as a suicide bomber. When General Quinven was exposed using a captured Klingon mind-sifter, Cartwright and the other members of the military cabal were exposed and dealt with while Valeris was killed by Saavik. (TOS - Mirror Universe novel: The Sorrows of Empire)