I think the worst one I’ve seen recently was
John Carter. It was apparently based on a really old book. Terribly unfocused movie, though. I felt like there was a lot of potential that was completely ignored. This is a story in which immortal beings are manipulating all of the civilizations on Earth and Mars for their own mysterious purposes, and yet they don’t explore their motives or nature at all, they just focus on the generic love story between the leads and lots of fighting with swords. Which is OK, mind you, but I really wanted to know why immortal beings were building and destroying nations willy-nilly.