Ross Webster is the head of Webscoe Industries and one of the wealthiest industrialists in the world. An eccentric (his tower had a ski lodge on the roof), he is often prone to quirky comments. Way down in one of his many organizations, an incident involving stolen funds by a computer hacker named Gus Gorman is brought to Webster's attention. Gorman is brought to his office, where Webster quizzes the hacker about his $85,789.90 paycheck and realizes that what he has on his hands is not a criminal, but a genius who can be of great value. Rather than send him to jail, he gives Gorman the option of working for him personally.
With Gorman's assistance, Webster seeks to monopolize the entire coffee industry by destroying Colombia's crops. He sends Gorman to one of Webscoe's subsidary companies in Smallville, Kansas to create a computer program using the available weather satellite. From this, a massive storm converges over Colombia. But Superman intervenes, however, flying into its midst to undo all the damage the storm caused, upsetting Webster's plans in the process.
Webster's next idea - in order to proceed and to use Gorman's talents - is to get rid of Superman, and the only way to get rid of Superman is to re-create, by computer, Kryptonite. Gorman does this, but instead of killing Superman, the end product made him evil, though nonetheless put him out of the way. In the meantime, Webster executes a new plan to deactivate all of the oil pumps in North America and reroute the oil tankers to the middle of the Atlantic ocean. To do this, he requires Gorman's help, yet again. But Gorman refuses unless Webster builds the hacker a state-of-the-art supercomputer he'd been secretly designing. Webster agrees. However, the Man of Steel comes back to thwart Webster's machinations once more. At their Grand Canyon hideout, Webster, his sister Vera, and Lorelei Ambrosia, along with Gus Gorman, set out to further his plans for economic control and to lure Superman into a trap. Superman does arrive, and enters a fierce bout with the newly constucted Ultimate Computer's Kryptonite ray and Vera Webster's transformation into a vicious cyborg. Just when Ross Webster seemed about to succeed, Gorman turned on him, helping Superman destroy the computer instead.
Effectively bringing an end to Webster's scheme, Superman never apprehended the defeated mastermind, leaving his whereabouts from that point on unknown.
- The character of Ross Webster was originally written for the films. Lex Luthor was not present in Superman III, partly due to the producers not wanting to keep reusing the same villain and have the same plot of constantly breaking out of jail akin to horror movies where a serial killer keeps coming back from the grave. Brainiac had been considered as the original villain for the script of the third movie. While that idea was eventually scrapped, some parts of the script made the final cut, namely domination of the world through control of computer systems. Another reason for the new script was Gene Hackman's apparent dissatisfaction with Alexander and Ilya Salkind's firing of Richard Donner midway through the shooting of Superman II, and expressed his displeasure by refusing to do any more Superman movies. However, Ilya Salkind later denied any ill will between himself and Hackman, saying that Lex Luthor was not present in the third movie for a couple of reasons; Gene Hackman had already committed himself to another movie in 1983 and was unavailable for filming and that there was little interest in recycling Lex Luthor as the trademark "bad guy". Hackman did, however, reprise his role as Lex Luthor in Superman IV, of which the Salkinds had no participation.
- Ross Webster has not made any further appearances, but the concept behind Superman III was reused for a 1988 video game, Superman, made by Kemco for the Nintendo Entertainment System. One chapter has Superman looking for a kidnapped professor of information technology. When the professor is rescued, he says he was forced to program a supercomputer to do the evil bidding of the bad guys, and if not stopped, that Ross Webster will control the world's economy. However, the boss of the stage Superman fights after disabling the computer is Jay Falk, not Webster. Also, Webster's name is misspelled as "Loss Webster".