There are only two movies for which I actually regret paying admission.
The first was Event Horizon.
I was lulled in by the first act, set aboard the high-gee rescue vessel, thinking it might actually be a good hard-SF film, like Aliens. But then, it started sucking. Like the hard vacuum of space. Not only did the premise turn out to be the stuff of juvenile horror comics, but the acting and characterization but the poor acting and veneer-thin characterization compounded the suckage.
By the time one astronaut, well aware of supernatural dangers aboard ship, is lured into the engine room of the possessed ship by a vision of someone thirty astronomical units away, I was ready to walk out.
The second was The Shape of Things starring Rachel Weisz, who also starred in the London stage version. Perhaps as a play, it may have worked. But I can’t believe Ms Weisz’ acting was any better on stage. And again, part of the premise depends on the main characters behaving the way they did, i.e., stupid and unrealistic.
When Weisz’ character starts making lifestyle decisions for the male lead, such as informing him who his friends should be and what kind of clothes to wear, or food to eat, and suggesting plastic surgery, any reasonable person’s reaction would be “I’m gonna dump this controlling bitch.” And in the final scene, where she humiliates him so completely and devastatingly, the reaction one expects would be assisted by a baseball bat.
My wife and I actually DID walk out on that one, and complained to the manager of the theater. He reassured us that it would “get better,” so we went back to our seats. It never did.
(At least he gave us free passes afterwards, and we used them to see Frida, which was awesome.)