Joss Whedon has said that a sequel to The Avengers would need to be "smaller" and "more personal"

The Buffy the Vampire Slayer creator told SFX that he doesn't want a follow-up to "rehash" what worked in the first film.

Asked how Avengers 2 could top next month's superhero blockbuster, Whedon responded: "By not trying to. By being smaller. More personal, more painful.

"By being the next thing that should happen to these characters, and not just a rehash of what seemed to work the first time. By having a theme that is completely fresh and organic to itself."

Whedon joked that a sequel could take heed from crime classic The Godfather II "by having flashbacks to young Michael Andolini escaping Sicily to come to New York, where he will be called Corleone".

"Sequels are always better when that happens," he quipped.

Whedon added that he has strived to give each character in The Avengers, which brings together Iron Man, Captain America, Thor and Hulk, enough screen time to see "what makes them awesome".

"I want to know what makes them tick, what makes them flawed, what makes them fight - and ultimately, what makes them awesome," he explained. "I go to these movies for those moments when the heroes define themselves, either through action or deliciously overwritten speeches."

The Avengers (titled Marvel Avengers Assemble in the UK) opens in cinemas this April with Robert Downey Jr, Chris Evans, Chris Hemsworth and Scarlett Johansson leading the cast.

"People have made it very clear that they are fed up with movies where entire cities are destroyed, and then we celebrate," Whedon said, recognizing that of all of those things crashing into other things is an attempt to harness somewhat newly found visual effects.

"Now, I watched 'The Dark Knight' and I thought of that as riffing on the genre," he said. "That was a superhero movie as 'The Godfather.' And I was like, 'But I just still want to see a superhero movie!' We had just gotten the technology to make it awesome, and I wasn't ready to be post-modern about it yet."

There is an inherent clash that characterizes the genre, and Whedon is tapped into that discordance more so than the use of CGI. "You're in a constant state of being pulled both ways at all times," he said, "You're trying to make a populist film with fascist iconography that is just bigger, and better, and longer, and trying to break that down and find a weakness and humanity."

Ultimately, what Whedon finds important in his work (and what we will see in "Avengers: Age of Ultron" which he wrote and is currently filming in the U.K.) is that emphasis on humanity.

"People come in with a certain amount of emotional baggage," he said, "So, whether we're in our larvae stage or our decadent stage, I can't really say, but I try to make my superhero movies as if there's either never been one or there's only ever been them. I work with the idea that it's just a natural way for people to be, so that you still make a movie about people."