Using the same engine as Ultima VI: The False Prophet and following on from Worlds of Ultima I: The Savage Empire. The Avatar and Prof. Spector travel to the past using the moonstone where Percivall Lowell is setting up a space cannon to take volunteers to Mars. The cannon is sabotaged, sending many famous Victorian era people to Mars. A second cannon sends the Avatar among others to Mars to rescue them. Once there, the Avatar must also rescue the plant like Martians before he can bring the others back to Earth.