Superman III. I have actulaly seen it before but it was a loooooooong time ago, back when my age was still in single digits.
I'm not sure I have the words to describe it lol. There's so much wrong with it I'm not sure where to start. For one thing, what's up with the weird, jarring, constant tonal shifts throughout the film? It's like it was written by two different people who didn't communicate enough, or one person with rapid cycling bipolar disorder or something. It also has the least threatening bad guys in cinematic history who are so pathetic as villains I'm suprised Superman even pays them any attention at all. They're even more pathetic as villains when you remember that the villains of the previous film were mother-fucking Zod and his crew.
And why does the computer suddenly turn sentient with no build up and start turning people into Cybermen? Why does Pryor suddenly decide he doesn't want to kill Superman when earlier he had no problem handing him a lump of synthetic Kryptonite with the explicitly expressed intent of killing Superman with it and nothing has happened in between to make him change his ways? Why do the bad guys keep trying to kill superman in ways that everybody on Earth should know won't work when they know he hasn't been weakend by their Kryptonite? Why can Suprman survive in the vaccum of space but starts suffocating when trapped in a celophane bubble? How does the synthetic Kryptonite cause Superman to literally, not metaphorically, split into two people? How does the green man on the traffic light climb up and attack the red man, are traffic lights sentient in the DC univere? Why is there a single computer that controls weather sattelites, traffic lights, American Express ATM machines and department store billing services? Why is it night time when Richar Pryor is hacking and using said computer but it's daytime when the traffic lights go haywire, even though it's clearly meant to be happening at the same time? How can weather satellites manipulate the weather when they're only designed to observe it, what on board equipment is being used to create a tornado? Why are some of the special effects and sets worse than the last two films?
Also, was having Superman's first two major "evil" acts straightening the tower of Pisa and blowing out the olypmic flame really the best way the writers could think to show that Superman was turning evil? Oh how terrible, watch out everyone an unstopable alien with god-like powers has run amok and is commiting very mild acts of vandalism and gernally being a bit annoying, who will save us from this horror?! Even causing the oil spill was in no way close to being wrost thing an evil Superman could do. The world got off lucky.
So yeah, it's the kind of movie that makes you spend the whole running time going, "Wait...what? Why is...how did...what?"