The Inferno Project was a scientific undertaking proposed and executed by Professor Stahlman to drill through the Earth's crust in the hopes of accessing untapped gases to use as alternative fuel. It was beset by a variety of problems. Professor Stahlman was a very reckless man who insisting on pushing the experimental drill being used to its limits so as to finish ahead of schedule, and the drill also brought up a strange super-heated green slime whose touched turned people into subhuman creatures known as Primords. Despite these problems, disaster was averted when Sir Keith Gold ordered the drill shut down before it pierced the Earth's crust, whilst Stahlman turned into a Primord.
In the alternate universe, Inferno was an unmitigated disaster and spelled the extinction of all mankind and the complete destruction of the Earth when the drill pierced the crust, unleashing super-heated gases and fiery lava which covered the planet's entire surface.