Aetherium

A map showing the shaft down from the engine room into the Aetherium portal

The Aetherium was a strange alternate dimension that could be accessed at the bottom of the shaft in the center of the Great Engine Room beneath the ruins of Babylon.

The Babylonians were aware that they could enter Marduk's realm if they built a Great Engine that would later be dubbed the "Infernal Machine." Under order of Babylonian King Nebuchadnezzar, the Babylonians constructed this device to break the barrier between the two dimensions, which would allow Marduk to invade. Luckily, Nebuchadnezzar realized the monster’s true intentions and ordered the Machine destroyed. However, four human disciples of Marduk remained faithful to the beast and fled to different corners of the Earth with the Machine's four most essential parts, in order to protect them from destruction.

The Machine parts were reassembled in Babylon, with the reactivation of the engine in 1947, largely by Indiana Jones. He and CIA agent Sophia Hapgood were the first humans to enter the Aetherium in millennia.

The Aetherium was an absolutely bizarre place. It was made entirely out of otherworldly, alien machinery and a partially oxygenated atmosphere as well as shafts of a semi-liquid, semi-gaseous substance called "aether." One could swim through the aether like water, though it was harmful for any human to breathe it in for too long, resulting in death after several minutes.

The Aetherium pulsed everywhere with blue, blue-violet, and blue-green light. It was inhabited by harmless, glowing, winged fish-like creatures; dangerous tentacled creatures which floated in the air; and cat-sized, spiked, venomous, insectoid creatures. The part of the Aetherium which Indiana Jones explored appeared to consist of a central shaft leading down through a massive palatial chamber with tunnels and other cavernous rooms built around it; however, it is not clear if this chamber made up the entire Aetherium or just the only accessible portion of it. It seems likely that this was just a small segment of the whole Aetherium that had been contained inside our own reality by the Babylonians when they had first activated the Machine.

Jones observed that the Aetherium connected to small chunks of the normal world all of which appeared to be places where the parts of Infernal Machine had been hidden, including small, room-sized regions of Kazakhstan, Palawan, Mexico, and Sudan. By using a device called the “Tool from Beyond” (that Jones had discovered in a chamber) the barrier between the Aetherium and these chambers of reality could be broken down, allowing a Jones to breathe in ordinary Earth air and thereby reverse the adverse effects of the Aetherium atmosphere on the human condition. Breaking these boundaries, however, appeared to cause damage to the Aetherium, with the alien machinery and substance of the dimension transforming into the ordinary mud-brick ruins of Babylon when barriers between the external world and the Aetherium were dissolved.

Jones encountered Marduk, the intelligent being who ruled the Aetherium (of mysterious origins), on two occasions. Marduk, a large winged creature with a many-crested head, dismissed Jones as a mere mortal and attempted to kill him with aether blasts. Jones, however, reflected the light energy back at Marduk, causing the monster to flee.

When Marduk later fused its body with Hapgood's, the result was a colossal bird-like humanoid. Jones again fought back and defeated the monster, releasing Hapgood's body. However, the Aetherium's structure, weakened from Jones's breaking of the boundaries between the Aetherium and reality, suddenly began to implode. Jones and Hapgood fled as the crumbling Aetherium erased itself from existence. The entrance to it which Indy and Sophia had exited by transformed into a stone wall behind them as they re-entered reality. It is believed that the weakened Marduk either perished in the collapse or was able to also enter reality, but unable to survive in it because of its non-aetheral atmosphere.

Appearances

• Indiana Jones and the Infernal Machine