I'm going to go ahead and say Superman III is an underrated sequel.

Yes, yes, I know -- Richard Pryor's character isn't in anyway believable as a computer genius and Robert Vaughn's character is just a carbon copy of Hackman's Luthor. The villains are dumb, plain and simple.

On the other hand, I find Annette O'Toole's Lana Lang a far better love interest than Margot Kidder's Lois, and I prefer how Clark is portrayed more as an actual human character in this film rather than as a mere disguise of Superman's like in the rest of the Chris Reeve films.