Cast: Larry 'Buster' Crabbe, Carol Hughes, Charles Middleton, Frank Shannon, Anne Gwynne
Running Time: 19 mins.

Dr. Alexis Zarkov perfects his 'N - Ray' that harnesses the energy of Nullitrion which can be used to neutralize and render useless Emperor Ming's power plant. The perfect place to fire the 'N - Ray' is from Devil's Dome in the Land Of The Dead. Learning of their plans, Ming directs soldiers in the area to plant a powerful time bomb on the Devil's Dome. Completing their mission, Ming's soldiers are captured by the Rock Men who live there. Flash and his companions, unaware of the bomb, make for Devils Dome and Rock Men now turn their attention to Flash and his group invading their territory. Will Flash discover the Bomb in time? Who are the Rock Men?