When the Deluxe Edition of Superman III was released, I was disappointed that they did not release an extended cut. There is an unofficial TV edition of Superman III that includes deleted scenes edited back in. That’s the version I like to consider the true version.
The DVD does offer some of the deleted and extended scenes that are in the TV edition:
SAVE MY BABY! - During the opening credits, Superman distracts some construction workers and a heavy pail drops into a park with a kid on a seesaw. The pail launches the kid into a tree and Superman rescues him.
TO THE RESCUE - An extended version of the chemical fire scene.
MAKING UP - Vera and Lorelei “shake hands”.
GOING TO SEE THE BOSS - Gus is not eager to meet Mr. Webster; so, he chats briefly with Mr. Webster’s secretary instead.
HATCHING THE PLAN - Ross explains the meaning of “Bubba” and Lorelei presents Ross with one of the mechanical penguins from the opening credits.
THE CON - Gus learns that Brad used to be called, “The Smallville Flash.” Note that in a later scene, Gus refers to him as the “Philly Flash” since he’s too drunk to remember correctly.
ROOFTOP SKI RESORT - Extended rooftop scene.
BOSS WANTS THIS TO GO - Gus brings the printout generated by the Vulcan Weather Satellite to a lab technician.
SUPERMAN HONORED - Superman is presented with the Smallville cookbook.
GUS' SPEECH - Gus ends his speech with a funny grunt.
HANGING UP ON BRAD - Brad calls twice instead of once.
There were additional scenes:
In the opening credits, construction workers accidentally obtain the stolen money bag.
When Jimmy first sees the burning chemical plant on the bus, he exclaims to Clark, “What a sunset!” Clark responds, “At 3 in the afternoon?”
When Gus explains his idea of the Ultimate Computer to Ross, he remarks that IBM doesn’t have anything like his machine. Also, after Lorelei correctly identifies the scraps of paper as computer plans, she pretends to be a bimbo again and asks if it’s plans for a hairdryer.
I can’t believe they omitted this from the DVD, but there was scene were Vera couldn’t read in bed because Lorelei and Superman were making out in an adjacent room.
Ballooning down to the Grand Canyon cave was longer.
There was a scene in a surgery room that occurs when the Ultimate Computer disables the US power grid. I can understand why this was deleted. It suggests that people are dying as a consequence of the Ultimate Computer.
There is an extended version of the scene where Clark presents Lana with the ring. Before entering her hotel room, Clark does a comic knock. And after launching Brad into the elevator on the food tray, someone in the elevator comments they understand why they sent it back.
The DVD also contains the Making of Superman III (1983), which is actually quite entertaining. The DVD commentary contains some interesting facts. For instance, there is a long-running rumor that Margot Kidder was given less than a dozen lines in this movie after she vocally expressed her discuss over the firing of the original director of Superman II. But, according the commentary, that is nonsense and they actually just wanted to avoid rehashing the old Superman saves Lois Lane storyline. The commentary also thanks Office Space (1999) for paying homage to Gus’ salami slicing scheme. Also, they mention that the movie actually did earn a lot of money despite it’s bad reviews; hence, they were allowed to make Superman IV (1987).