Joss Whedon has said Star Wars: The Empire Strikes Back had a bad ending.
The Avengers Assemble director has previously cited George Lucas' famous franchise Star Wars as an example of sequels that got it right. But he has now told Entertainment Weekly that The Empire Strikes Back "betrayed my trust" by not having an ending.
Joss said: "Empire committed the cardinal sin of not actually ending. Which at the time I was appalled by and I still think it was a terrible idea.
"It's not an ending. It's a Come Back Next Week, or in three years. And that upsets me. I go to movies expecting to have a whole experience. If I want a movie that doesn't end I'll go to a French movie. That's a betrayal of trust to me. A movie has to be complete within itself, it can't just build off the first one or play variations."
The Buffy The Vampire Slayer creator also had a go at hit teen franchise Twilight for emancipating its lead female character, while he had made his heroine Buffy empowered.
Joss said: "The thing about Buffy for me is - on a show-by-show basis - are there female characters who are being empowered, who are driving the narrative.
"The Twilight thing and a lot of these franchise attempts coming out, everything rests on what this girl will do, but she's completely passive, or not really knowing what the hell is going on.
"And that's incredibly frustrating to me because a lot of what's taking on the oeuvre of Buffy, is actually a reaction against it. Everything is there - except for the Buffy. A lot of things aimed at the younger kids is just Choosing Boyfriends: The Movie."