Machine World is one of the 11 Braneworlds other than our own, which is referred to as the Human World. Machine World is home to giant vehicular beings called Engines who wage a war against the Gaiark, who desire to pollute their world. Losing, Gaiark's three Pollution Ministers escape to Earth, seeing the Human World as an easier location to create their ideal paradise. The six Engines manage to pursue them, selecting five humans to become their partners, the Engine Force Power Rangers. The team are later joined by the Engine Wing Rangers and their Wing Engines, as well as the Ancient Engines. Together they battle the Gaiark and other evil villains from other Braneworlds.
